There has been news about the oncoming policy for solar rooftop in Delhi,Gujarat, Tamilnadu etc., Keeping in mind the interest generated, i have collated some info.
Roof-top Solar Installations
Rooftop Photo Voltaic (PV) installations are one of the major off-grid solar energy utilization schemes. One of the best features of rooftop solar PV systems is that they can be permitted and installed faster than other types of renewable power plants. They’re clean, quiet, and visually unobtrusive. New generations of PV roofing products utilize designs that allow them to be integral parts of the roof, providing both electricity and shelter from the elements.
Solar Energy incentives in most of the developed solar markets in Europe have clearly shifted their preference to distributed small rooftop solar installations on residences. This is because it reduces the need for expensive power generation infrastructure, improves reliability and puts money in the hands of the common citizens.
Spain, Germany and Italy which are the 3 biggest markets in the world have done this. India however has not paid any focus to rooftop solar installations except for Delhi. Electricity in India is not only expensive but also highly unreliable and of low quality. Low voltages and blackouts of 10 hours are not uncommon.
Having a reliable home based source of power would be attractive to most people in India even at higher costs. It would also lead to reduced losses in the power transmission which is the highest in the world at around 30%.The advantages of promoting residential solar is much more however the policymakers have not given enough thought with half of the subsidies going to Solar Thermal Technology which is fast losing out to Solar PV technology.
India’s solar policy makes it clear that the decision makers do not have enough knowledge about the developments in this fast paced solar energy sector to make the optimum decisions.
Solar Panels in India are also being promoted through domestic content requirements however this policy also might not make a lot of sense. Solar Panel Manufacturing is fast becoming a commodity industry with low margins with the biggest Solar Panel Manufacturers expected to survive a global shakeout. It remains to be seen it develops as a global hub or remains a subsidy driven industry catering only to local needs without any competitive advantage.
For off-grid connectivity, many organizations round the globe are incorporating Roof-top installations and analyzing their performance based on the feasible and efficient types. For example, in US, National Institute of Standards and Technology (NIST) working on the system, located it on the flat roof of NIST’s Administration Building which successfully produced NIST’s first site-generated renewable energy on September 14, 2001.
At its new Roof Photovoltaic Test Facility, it is monitoring the electrical performance and thermal performance of seven different residential systems designed for sloped roofs and two commercial building units designed for flat, industrial roofs. The data will be used to evaluate and improve computer algorithms for software simulation programs that predict the installed energy production of photovoltaic roof installations.
Why Rooftop Solar
- Increasing demand for electricity
- Heavy load shedding by utilities in many cities and towns
- Rising cost of fuel for diesel generators
- India is endowed with abundant solar radiation
- Effective utilization of building space
- Availability of incentives
- Electricity cost savings and inflation free electricity for long periods of time
- Reducing carbon footprint
Advantages and Disadvantages of Rooftop Solar vs Large Ground Mounted Solar Plants
Advantages
1) Long Delays in Permitting, Environment Clearance, Land Siting – Large Solar Farms have to go through a myriad of regulations and clearances. There have also been instances of lawsuits against solar thermal and solar pv plants in California by wildlife and environmental groups as well as local Indian tribes.
2) Electricity Transmission Costs – Grid Connection leads to additional costs for solar farms while rooftop solar can use existing transmission infrastructure
3) Less Grid Stability – A Large Part of Distributed Solar is consumed locally while Farms supply 100% to the grid. That makes managing the grid difficult when solar penetration increases
Disadvantages
1) Lower Cost and Scale – The greater scale of these plants allows lower installations compared to smaller installations. The costs are reduced in permitting, maintenance as well.
2) Use of Disturbed Land – Solar Farms can be built on disturbed land like in Germany where they have been built on former airbases.
3)Utility Friendly – Large Solar Farms are controlled by utilities or IPPs while rooftop solar is generally in the ownership of residential owners or commercial owners. This results in less pushback from utilities which generally control tranmission and allow easier acceptance of solar energy.
Types:
Sloped or Pitched Roof Mount Solar Panel Arrays
Rooftop solar panel array installations are the most popular type of solar panel array, it simply requires a southern exposure for optimum performance. Its earning potential is limited by pitch of the roof, angle off of due south and most importantly, shading. The metal flashing mounts that are used to install the panels ensures a watertight mount and strengthens to withstand extreme winds and harsh climates. The screw attachment to the roof stud is under the asphalt shingle and sealed, then covered by the asphalt shingle. The rails bolt onto the flashing and the panels are then mounted together in rows.
Non-Penetrating Ballasted Roof Mount Solar Panel Arrays
Most commercial buildings have flat membrane style rooftops which makes an ideal platform for a solar array. The array can be set at 30 degrees and exactly due south for great returns. There are no roof penetrations and these ballast mounted rows link together. The metal stands are placed on special pads and then concrete patio blocks are laid in each corner.
Costs
Capital Cost
Solar PV has one of the highest capital costs of all renewable energy sources, but it has relatively low operational costs, owing to the low maintenance and repair needs. The precise cost depends on scale. This includes the cost of panels, the balance of systems, the cost of land/installation area (in case of rooftop PV) and other support infrastructures.
The total Installation costs involved without battery is detailed:
Component with specification (1.5 KW Residential Roof Top without Battery)
|
Cost (INR.)
|
PV module (12 V, 75 Wp) * 20 No's
|
1,01,250
|
Steel mounting materials, cables & installation accessories
|
42,250
|
Other BoS
|
16,250
|
Power Conditioniing Unit
|
81,250
|
Total Hardware Costs
|
2,41,000
|
Margins (Company)
|
24,100
|
Margin (Dealer / Distributor)
|
36,150
|
Total Retail Cost
|
3,01,250
|
VAT and Duties
|
30,125
|
Installation
|
11,000
|
Installed Cost
|
3,42,375
|
The Total installation costs by incorporating Battery backup is detailed:
| |
Component with specification
(1.5 KW Residential Roof Top with Battery)
|
Cost (INR.)
|
PV module (12 V, 75 Wp) * 20 No's
|
1,01,250
|
Steel mounting materials, cables & installation accessories
|
42,250
|
Storage battery (Lead Acid Battery) 12 V, 80 A * 10 No's
|
71,500
|
Other BoS
|
16,250
|
Power Conditioning Unit
|
81,250
|
Total Hardware Costs
|
3,12,500
|
Margins (Company)
|
31,250
|
Margin (Dealer / Distributor)
|
46,875
|
Total Retail Cost
|
3,90,625
|
VAT and Duties
|
39,062.5
|
Installation
|
11,000
|
Installed Cost
|
4,40,687.5
|
Operational Cost
Solar PV has no moving parts. As a result electricity generation from solar PV has very low operating costs. An approximate estimate of operating costs for solar PV is 0.5 Rs per KWh (one unit) of power generated. Insurance costs add about Rs 0.15 to 0.2 per kWh, so the total operating costs including insurance is about Rs 0.65-0.7/kWh.
Government support
The government of India is promoting the use of solar energy through various strategies. In the latest budget for 2010/11, the government has announced an allocation of Indian INR 10 billion (US$223 million) towards the Jawaharlal Nehru National Solar Mission and the establishment of a clean energy fund. It is an increase of Indian Rupee symbol.svg3.8 billion (US$84.7 million) from the previous budget.
This new budget has also encouraged private solar companies by reducing customs duty on solar panels by 5% and exempting excise duty on solar photovoltaic panels. This is expected to reduce the cost of a roof-top solar panel installation by 15–20%. The budget also proposed a coal tax of US$1 per metric ton on domestic and imported coal used for power generation.
Additionally, the government has initiated a Renewable Energy Certificate (REC)[47] scheme, which is designed to drive investment in low-carbon energy projects. The Ministry of New and Renewable Energy provides 70 percent subsidy on the installation cost of a solar photovoltaic power plant in North-East states and 30 percentage subsidy on other regions. The detailed outlay of the National Solar Mission highlights various targets set by the government to increase solar energy in the country's energy portfolio.
Customers and Benefits under Indian Policies:
The Indian government is about to launch roof top solar policy in capital state Delhi. The policy aims to encourage people to switch to renewable energy sources. The house owner will easily be able to earn about 19 per cent returns on his investment.
In nine years, the returns will go further up. There will also be an income tax rebate on this investment. According to the policy, house owners would have the option of either paying 30% of the total cost of installation or can lease their roof to a solar power developer, who would then set up a unit.
The remaining 70% would be financed by banks. The home owners would have to sign power purchase agreements with the state distribution companies for getting the approval for feeding power into the grid. Home owners will get to earn Rs.17 ($0.38) per kWh of power produced through the solar panels, which will be directly fed into a grid. They can sell the power for 25 years. The government plans to generate 20 MW through solar energy over the next three years. The government is working out modalities of the scheme’s benefits.
The discoms may even deduct the amount the house owner earns through the solar unit from the electricity bill. The discoms are also expected to benefit from the scheme since the power purchased from the these units would be costly, discoms would get subsidy of Rs. 13 per unit form the government. According to the recent estimate, cost of setting up a 5-KW unit is around Rs 7.5 lakh ($16,600) and requires 2,000-2500 sq feet of roof space. After signing a Power Purchase Agreement with the discoms, the home owner would have to pay Rs 3 lakh ($6640), on which they would get returns of close to Rs 60,000 ($1330) per annum.
The scheme would also help the Delhi government to fulfill its solar energy purchase obligation which requires states across India to source at 0.25% of their power consumption from solar power plants, starting 2013. The state governments are also required to increase solar power’s contribution to 3% by 2022. States like Delhi, where land availability is major issues, rooftops can contribute significantly in terms of solar energy capacity addition.
The policy is a significant effort towards bringing affordable, even profitable, clean energy technologies to the community. Such policies would help tap millions of square feet of roof space area across the country for generating solar power.
National Solar Mission Guidelines for Off-Grid and Decentralized Solar Applications & Rooftop and Other Small Solar Power Plants
Incentives announced:
Solar PV
| |||
Condition
|
Subsidy
|
Capital Subsidy
|
Special Regions
|
Grid connected projects at least 100 kW and up to 2 MW, connected to HT level [below 33 kV] of distribution network
|
A GBI is payable to the project developer. Its value is the difference between the tariff determined by the CERC (17.9 for solar PV and Rs 15.4 for solar thermal) and the base rate, which is equal to Rs 5.5 per kWh for the financial year of 2010 to 2011, and escalates @ 3% every year.
| ||
For off-grid / rooftop solar PV installations of a maximum capacity of 100 Wp per site, and for mini-grids for remote electrification with a maximum capacity of up to 250 kW:
|
Subsidy, which is calculated on the basis of a cost benchmarked by MNRE, is notionally equal to 30% of benchmarked cost of solar power systems. For 2010 it is fixed at Rs. 90 per Wp with battery storage, and at around Rs. 70 per Wp without battery storage.
|
Solar PV plants in micro-grid mode/local distribution network, to meet unmet community need for power in unelectrified rural areas, will be provided a capital subsidy of Rs 150/ Wp
|
In special category states, viz. NE, Sikkim, Himachal Pradesh, and Uttarakhand, a capital subsidy of up to 90% of installation cost can potentially be availed.
Moreover, in difficult-to-reach areas such as Lakshadweep, Andaman and Nicobar Islands, and districts on India’s borders, the subsidy availed will also be 90%
|
In addition to the above, the debt portion of investment can be financed by a soft loan at 5% interest rate, to be availed from the IREDA.
| |||
Solar CSP
| |||
Off-grid solar CSP installations of a maximum capacity of 100 Wp per site, and for mini-grids for remote electrification with a maximum capacity of up to 250 kW
|
Subsidy, which is calculated on the basis of a cost benchmarked by MNRE, is notionally equal to 30% of benchmarked cost of solar power systems. For 2010 it is fixed at Rs. 90 per Wp with battery storage, and at around Rs. 70 per Wp without battery storage.
|
In difficult-to-reach areas such as Lakshadweep, Andaman and Nicobar Islands, and districts on India’s borders, the capital subsidy availed will be 60% of benchmarked costs for solar thermal installations.
| |
Subsidies on costs of CSP equipment: Rs. 3000 per sq. meter for Evacuated Tube collectors, 3300 for Flat plate collectors with liquid as the working fluid, 2400 for Flat plate collectors with air as the working fluid, 3600 for Solar collector system for direct heating application, 2100 for Concentrator with manual tracking, 3600 for non-imaging concentrators, 5400 for Concentrator with single axis tracking, and Rs 6000 per sq. meter for Concentrator with double axis tracking.
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Notes
- The benchmarked costs (of standard solar systems) will be changed every year.
- GBI = Generation based Incentives
Guidelines in Detail
The immediate aim of the National Solar Mission is to focus on setting up an enabling environment for solar technology penetration in the country both at a centralized and decentralized level. The first phase (up to 2013) will focus on capturing of the low hanging options in solar thermal; on promoting off-grid systems to serve populations without access to commercial energy and modest capacity addition in grid-based systems. In the second phase, after taking into account the experience of the initial years, capacity will be aggressively ramped up to create conditions for up scaled and competitive solar energy penetration in the country. On the 17th of June, 2010, the JNNSM’s guidelines for Off-grid, Rooftop, and all other small solar applications were announced by the Ministry of New and Renewable Energy (MNRE), and the guidelines for its other applications will be announced later. The MNRE’s deployment targets are:
Envisaged Deployment Across the Application Segments
| ||||
S. No.
|
Application segment
|
Target
| ||
Phase 1
(2010-13)
|
Phase 2
(2013-17)
|
Phase 3
(2017-22)
| ||
1
|
Solar Thermal collectors
|
7 million sq. meters
|
15 million sq. meters
|
20 million sq. meters
|
2
|
Off grid solar applications
|
200 MW
|
1000 MW
|
2000 MW
|
3
|
Grid Power, including Rooftop and small plants
|
1,000 MW
|
4,000-10,000 MW
|
20,000 MW
|
To achieve these ends, the JNNSM’s stated objectives are to create awareness, promote solar PV and solar CSP applications for meeting phase I targets, support industry players, to create the paradigm shift which is necessary for commoditization of off-grid solar applications etc.
The JNNSM’s announced small solar scheme has 2 parts:
(1) off-grid, and
(2) grid connected (minimum of 100 kW and up to 2 MW, connected to HT level [below 33 kV] of distribution network).
Off-grid Solar
The scope of the scheme for off-grid has been defined as covering only installations of a maximum capacity of 100 Wp per site, and for off-grid solar CSP applications to meet requirements like lighting, electricity/power, heating/cooling energy requirements. However, for mini-grids for remote electrification, applications up to a maximum capacity of 250 kW will be supported.
Incentives offered by the JNNSM for Off-grid Solar
In the domain of manufacturing, to promote technology up-gradation and facility expansion, soft loans, including a working capital component, will be made available by the IREDA to small manufacturers of solar thermal systems and balance of systems manufacturers for solar PV systems (excluding battery manufacturers). However, the JNNSM is designed mainly to address the need for incentives of project developers and installers who deal with solar applications:
- Standalone Solar PV and Solar CSP power systems
Funding will be on the basis of submission of a project report which would include client details, technical and financial details, O&M, and monitoring arrangements. The project will be funded by a mixture of debt and equity, and the promoters’ equity contribution must be at least 20%. The subsidy will be dispensed as a combination of 30% subsidy and/or soft loan bearing 5% interest. Note: Subsidy percentage is calculated not as per real cost, but cost benchmarked by MNRE, whereby the value of the subsidy, which is equal to 30% of cost of systems is estimated at Rs. 90 per Wp (with battery storage), and at around Rs. 70 per Wp (without battery storage). The benchmarked cost of standard solar systems will be changed every year.
With effect from 01.04.2011 the benchmark cost for photovoltaic will be revised to Rs. 270 per Wp (with battery) and Rs. 190 per Wp (without battery bank) respectively. For general areas the CFA would be 30% limited to Rs. 81 per Wp (with battery back-up) and Rs. 57 for systems (without storage battery). For Special category states/North-East States the CFA would be 90% limited to Rs. 243 per Wp (with battery back-up) and Rs. 171(without battery back up).
Standalone SPV plants with battery storage in micro-grid mode/local distribution network, to meet unmet community demand for power in un-electrified rural areas, will be provided a capital subsidy of Rs 150/ Wp and soft loans at 5% interest rate. However, in special category states, viz. NE, Sikkim, Himachal Pradesh, and Uttarakhand, a capital subsidy of 90% will be availed. Moreover, in difficult-to-reach areas such as Lakshadweep, Andaman and Nicobar Islands, and districts on India’s borders, the subsidy availed will also be 90% for solar PV installations, but only 60% for solar thermal installations. 100% of real cost could be subsidized by the government in case of novel and innovative application of solar systems.
Agencies Involved in the Scheme’s Implementation
The scheme’s implementation will be undertaken in an ecosystem consisting of various “channel partners”, which include:
1) Renewable Energy Service Providing Companies – RESCOs (installers of RE systems) – may tie up with FIs for accessing financial support.
2) Financial Aggregators: Financial Institutions such as microfinance institutions involved in customer finance, having established base of operations in rural and urban areas, and outreach through self-help groups etc. These typically access interest subsidy through refinance ability, as well as credit linked capital subsidy (on behalf of their borrowers) from IREDA.
3) FIs (Financial Integrators) integrate different sources of finance including carbon finance (CDMs), government assistance, and other sources of funds, to design financial instruments and products, making them affordable to manufacturers and RESCOs, with whom they'll tie up.
4) System integrators provide various RE systems and services to clients, such as design, supply, integration, and installation, O&M etc. They may tie up with FIs for accessing financial support.
5) Program administrators such as state, government ministries and departments, SNAs etc.
The various channel partners will be selected on the basis of net worth/turnover, credit rating, track record, technical capability for undertaking projects (site selection, feasibility study, design/value engineering, cost optimization, time scheduling, procurement, installation, commissioning, and O&M activities, and tie-ups with equipment providers in general. Young entrepreneurs will be favored.
Grid-connected Rooftop and Small Solar Plants
The Rooftop PV and Small Solar Generation Program (RPSSGP)
These guidelines are effective for projects which are at least 100 kW and up to 2 MW, connected to HT level [below 33 kV] of distribution network. Capacity addition in such projects to the tune of 90 MW is planned by the government. GBI (generation based incentives) will be payable to the distribution utility for power purchased from solar power project selected under these guidelines, including captive consumption of power. The GBI will be the difference between the tariff determined by the CERC (17.9 for solar PV and Rs 15.4 for solar thermal) and the base rate. Base rate is equal to Rs 5.5 per kWh for the financial year of 2010 to 2011, and escalates @ 3% every year.
IREDA, in the capacity of “Program Administrator”, will be responsible for registration of projects seeking GBI (Generation Based Incentives) and distribution of GBI. “State Competent authorities” will be announced by state governments. The project developer’s job will be to preregister with the state competent authority, finalize a memorandum of understanding with the local utility, register with the Program Administrator to participate in the RPSSGP, and intimate the Program Administrator about the achievement of milestones, along with supporting documents.
Eligibility Criteria
Technical: PV modules and other subsystems proposed to be used must comply with relevant IEC/BIS standards and/or applicable standards as specified by the Central Energy Authority. Crystalline Silicon based projects are mandated to source their modules from India itself, while no such restrictions are imposed on other technologies. For Solar CSP, the technology must be “accepted” – it must have been demonstrably working for 1 year elsewhere. The plant should be designed for grid connectivity at H-T level at the nearest substation.
Layman’s perspective:
A Typical rooftop of 1 kw solar system for a house: good enough for a layman to understand.
The 1 kw system could provide backup for:
a). 3 fans+3 tubelights+1TV (4 hours)
b). 1 Ton of AC (2 hours)
c). 1 PC (2 hours)
b). 1 Ton of AC (2 hours)
c). 1 PC (2 hours)
The cost of system will be around 1.9-2 lacs, with MNRE subsidy of 30% the cost would come down to 1.1-1.2 lacs.
Technical considerations:
The popularity of rooftop photovoltaic (PV) panels has exploded during the past decade as Building Teams look to maximize building energy efficiency, implement renewable energy measures, and achieve green building certification for their projects. However, installing rooftop PV systems—rack-mounted, roof-bearing, or fully integrated systems—requires careful consideration to avoid damaging the roof system. Improper handling, storage, and installation of the PV panels can cause damage to the roof, which can lead to moisture intrusion, wind uplift problems, and even structural damage. In addition, rooftop PV systems should be designed with future maintenance, roof repairs, and fire-suppression efforts in mind. The technical constraints and respective considerations are as following:
1. Verify the fire rating of the rooftop photovoltaic system. Most rooftop PV systems qualify for a Class C fire rating, while most of the roof coverings over which these systems are installed are fire rated Class A or B. The fire rating, especially spread of flame, is critical, especially for roof-bearing and rack-mounted systems. For instance, Building Teams may need to take steps like incorporating half-inch gypsum board into the assembly to obtain the proper fire rating. For sloped roofs, it is especially important to confirm that the required fire classification is available at the slope required. For instance, standing-seam metal roofs routinely qualify as Class A fire-resistant on unlimited slopes, whereas the same standing-seam metal roofs covered with thin-film, flexible PV panels have significant slope restrictions.
2. Flashing detail is critical for maintaining the warranty. Flashing detail work must be performed by a contractor approved by the roof membrane manufacturer. Building owners must get such permission in advance from the roofing manufacturer or the warranty may be voided. The main concern is keeping a record of alterations to the roof system. For example, if a manufacturer gets a leak call immediately after an alternation is completed, they might know where to start looking for the leak.
3. PV systems must be properly marked. Marking is needed to provide emergency responders with appropriate warning and guidance with respect to working around and isolating the solar electric system. Proper marking helps responders identify energized electrical lines that connect the solar modules to the inverter. Materials used for marking must be weather resistant and should be placed adjacent to the main service disconnect in a location clearly visible from the location where the lever is operated.
4. Make sure to protect the roof system while handling PV panels. Damage to roof systems, especially single-ply membranes, often occurs during the handling of the PV panels. Four tips for avoiding roof system damage while moving and storing PVs:
• Store boxes PV units over joists to avoid deflecting the metal deck.
• If boxed units are palletized, place a cushion layer of plywood between the pallet and the roof surface.
• Do not point-load the roof surface by placing the corner of a hard panel directly on the surface.
• Use moving equipment fitted with pneumatic tires to transport equipment and materials over the finished roof surface.
5. In retrofit projects, consider roof life before installing PVs. Due to potentially high costs associated with temporarily disconnecting and moving PV panels to execute roof repairs, Building Teams should assess the remaining life of the existing roof covering as part of a PV project. Serious consideration should be given to replacing the existing roof covering as part of a PV project. At the very least, one should investigate and repair roof leaks and perform any preventive-type maintenance work, even if it is not scheduled to be performed for a couple of years.
6. Pay close attention to the location of direct current (DC) conductors. Conduit, wiring systems, and raceways for photovoltaic circuits should be located as close as possible to the ridge or hip or valley and from the hip or valley as directly as possible to an outside wall to reduce trip hazards and maximize ventilation opportunities. DC combiner boxes should be located such that conduit runs are minimized in the pathways between arrays. To limit the hazard of cutting live conduit in venting operations, DC wiring should be run in metallic conduit or raceways when located within enclosed spaces in a building and should be run (to the maximum extent possible) along the bottom of load-bearing members.
7. Provide for fall protection in certain cases. In retrofit projects, if the PV modules direct foot traffic to within six feet of unprotected roof edges or roof openings, fall protection provisions, such as guardrails and roof hatches, are a must.
8. Configure PV arrays to allow access for future maintenance, roof repairs, and fire-suppression efforts. A minimum of six feet of clearance along the perimeter of the roof should be given and at least four feet around roof access hatches and skylights. Also, pathways should be provided along the centerline of both axes of the roof. Locate these pathways over structural members.
9. Make sure integrated PV panels can handle high winds. For semi-rigid PV panels adhered over mechanically attached single-ply roofs, it is needed to make sure that the PV panels can accommodate billowing of the singly-ply membrane during high-wind conditions without incurring damage, such as cracking, splitting, or rupture. Install air retarders and supplemental membrane fasteners around each PV panel to help avoid damage.
Installation Steps and Guidelines:
VS System Components
1. L-Feet:The Renusol VS L-foot inserts anywhere without sliding and quickly secures the rail where needed. The bolt alignment indicator on the end of the screw ensures the L-foot is properly secured and won't compromise the structure of the panel design.
2. Rail : The rail is mounted with the L-foot and holds the end-clamp and the mid-clamp for the installation of the PV module as well as the rail connectors.
3. Splice connector: This piece is used to join several rails together. The rail connector is inserted into a premounted rail until it reaches the rivet. The rivet in the middle presets the rail gap for thermal expansion. No fastening required.
4. Mid-clamp : The mid-clamp can be snapped into the desired position of the rail section and holds the PV module. The height of the mid-clamp can be adjusted to the frame height of the module using a hexagon socket screw. The mid-clamp adjusts for panels 34 to 51 mm.
5. End-clamp
The end clamp is placed on the section at the end f the rail and holds the PV module. The end clamp can be adjusted to accommodate frame heights from 34 to 51 mm.
6. Anti-slip hardware
Anti-slip hardware makes module installation alignment easier and ensures modules stay in place.
Renusol CS60 Installation Steps:
A ballasted, non-penetrating system with easy installation for most current PV modules. 1 Renusol CS60 = 1 PV Module.
Renusol CS60 At A Glance
- Three simple installation steps
- Cost & planning efficient solution
- PV-mounting without roof penetration
- Low roof load
- Integrated airfoil minimizes ballast
- 1 Renusol CS60 = 1 PV Module
Further and detailed installations can be downloaded from:
http://www.renusolamerica.com/index.php?id=23
Maintenance and Troubleshooting:
Maintenance Steps
Step 1: At the Inverter :
Use a voltmeter and a DC ammeter to check and record the inverter’s operating DC input voltage and current level and on the AC side, and the inverter’s output voltage and current levels. Check that the appropriate LEDs are lit up to indicate proper operation of the inverter. If the inverter can display the total kWh produced since it first started up, record the amount. Use this number to compare the PV system’s production since the last inspection.
Step 2: On the Roof:
Note and record the condition of the modules. Look for signs of degradation (for example, color changes, fogged glazing, de-lamination, warping, or water leaks), cracked glazing, and bent frames on the modules. Tighten all loose nuts and bolts, holding the modules to the mounting rack and to the mounting clips. Secure any loose wiring under the modules. Check the wiring for signs of chewing by squirrels, and look for cuts, gashes, or worn spots in the wiring’s insulation. Replace any damaged wire runs. Check the frame ground connections between modules and from the modules to the junction box(es). Check to see that the sealants around all building penetrations are in good condition and repair if necessary. Open the junction box(es) and look for and correct any dirty, loose, or broken connections. Test the tightness of each connection and tighten all loose ones. Note any problems that can be corrected at a later time or at the next scheduled inspection time. Close the junctions box(es) and check that all conduit connections are tight. Remove all sources of shade on the array and rinse the array to remove the accumulated dust, dirt, and other debris. Some debris, such as bird droppings, may need to soak a bit to fully remove it.
Step 3: At the Combiner Box:
Open the combiner box and look for any dirty, loose, or broken connections, and correct as necessary. Use a voltmeter and DC ammeter to measure and record the array’s operating voltage and current level on the output side of the combiner box. Note the relative sun conditions at the time (i.e., full sun, partly cloudy, heavy overcast). Remove the fuses and then check and record each string’s open circuit voltage and current levels. Note any deviation between strings for future correction. The open circuit measurements can also be used to determine if the array’s output is degrading over time. Return the fuses and close the combiner box.
Step 4: Inside: Open all disconnect switches. Use the ohmmeter section of the voltmeter to check the grounding system connections. Greater than 25 ohms indicates that corrosion or a poor connection is present, which must be located and corrected. If opening the disconnect switch breaks the ground, rewire the switch to correct the problem. Check each of the disconnected sections for a ground-fault condition any that are found.
Step 5: Back at the Inverter
Turn the inverter off and check for dirty, loose, or broken wires and connections. Check for and repair any ground faults. Power the system up. Check for normal start up operation and that the inverter produces AC electricity.
System Troubleshooting
Troubleshooting a PV system usually means:
- A load does not operate properly or not at all;
- The inverter does not operate properly or not at all; or
- The array has low or no voltage or current.
A qualified electrician should check and correct electrical problems in a PV system, since homeowners are unlikely to be qualified to perform such work.
Troubleshooting: Load Problem
The first step is to check all switches. Are they turned off, or in the wrong position? If so, turn them on or put them in the correct position. Also check to see that the load is plugged in. With a voltmeter, check to see that the proper voltage is present at the load’s connection. Next check the fuses and circuit breakers. Are there blown fuses or tripped breakers? If so, locate the cause and fix or replace the faulty component. If there are no blown fuses or tripped breakers and the load is a motor, an internal thermal breaker may be tripped or there may be an open circuit in the motor. Plug in another load and note its operation. Check for broken wires and any loose connections. Clean all dirty connections and replace all bad wiring. With the power off, check for and repair any ground faults. Replace the fuses and reset the switches. If they blow or trip again, there is a problem short, which must be located and repaired. If the load does not operate properly, check the system’s voltage at the load’s connection. Low voltage could mean that the wire feeding the circuit is too small and too long and needs to be upgraded to reduce the voltage drop. The load also could be too large for the wire size in the circuit. Reduce the load on the circuit or run larger wire that is sized for the current load.
Troubleshooting:InverterProblem
A lack of power output from the inverter could be caused by a blown fuse, tripped breaker, a broken wire, a ground fault, or any of the inverter’s internal disconnects (high and low voltage and current). The load on the inverter may have too high of a current demand. Reduce the loads or replace the inverter with one with a larger output. With the power off, check for and repair any ground faults before starting the inverter again. The utility’s voltage and frequency are sensed by the inverter, which normally produces AC electricity at the same voltage and frequency. The AC current output from the inverter fluctuates with the level of solar insolation on the array. Low or high utility voltage sensed by the internal disconnects will cause the inverter to shut down. Contact the utility to correct the problem on its side. Inverter problems could also be caused by a problem on the array side of inverter that trips one of the internal disconnects.
A lack of power output from the inverter could be caused by a blown fuse, tripped breaker, a broken wire, a ground fault, or any of the inverter’s internal disconnects (high and low voltage and current). The load on the inverter may have too high of a current demand. Reduce the loads or replace the inverter with one with a larger output. With the power off, check for and repair any ground faults before starting the inverter again. The utility’s voltage and frequency are sensed by the inverter, which normally produces AC electricity at the same voltage and frequency. The AC current output from the inverter fluctuates with the level of solar insolation on the array. Low or high utility voltage sensed by the internal disconnects will cause the inverter to shut down. Contact the utility to correct the problem on its side. Inverter problems could also be caused by a problem on the array side of inverter that trips one of the internal disconnects.
Troubleshooting: Array Problem
Prior to getting on the roof, check and record the inverter’s input voltage and current level from the array. If the array is not producing DC electricity, check all switches, fuses, and circuit breakers. Replace blown fuses and reset the breakers and switches. A spurious surge may have passed through, tripping or blowing the protective devices. Check for broken wires and loose or dirty connections in the inverter. Replace all damaged wires and clean and tighten all connections. Visually check the array for obvious damage to the modules and wiring. Repair as needed and replace all damaged wiring. Having a fused combiner box can save a lot of time when checking each module or sub-array string. Remove the fuses and then check and record the open-circuit voltage and current reading for each circuit string. If the output voltage is low, it could indicate that some modules in the series string are defective or disconnected and need to be replaced. Defective blocking or bypass diodes in the modules may need to be replaced. Low voltage also could be caused by the wrong wiring connecting the modules in the string to the junction box or combiner box or the inverter. The wiring could be either sized too small or the wire run is too long for the string’s output current level. Upgrading the wire size for the current level should correct this problem. Low current output could be caused by cloudy conditions, a defective blocking or bypass diode, a damaged module, one or more parallel connection between modules in the string is broken, loose, or dirty, or some parallel connections the module are broken, loose, or dirty. Replace a damaged module or one with internal parallel connection problems. Replace defective diodes and clean and tighten all connections. Some of the array may be shaded, significantly reducing the array’s current output. Remove the shade source to regain the string’s full current output. Dirty modules also could cause reduced current output. Wash the modules to restore the array’s current output.
Business Prospects
Most businesses acknowledge the inherent benefits of using the sun to generate clean energy while, at the same time, saving on utility bills. However, there remains great uncertainty on how best to finance the initial capital required for the installation, operation and maintenance of integrated photovoltaic, hot water or thermal solar systems. The following is a simple, five-step guide for acquiring and/or installing a solar system:
1. Complete an energy efficiency audit. Most utilities provide free efficiency audits to businesses.
2. Engage an experienced integrator. Qualified integrators (or contractors that manage solar projects from cost-estimating through construction phases) are an essential component in securing the most productive solar energy system. Selection of the appropriate integrator will depend upon the financing model adopted. An integrator can often assist with selecting the right solar equipment, selecting financing, and applying for loans or incentives.
3. Select the solar equipment. Research and select the most appropriate solar system for business with the assistance of an experienced integrator—photovoltaic cell.
4. Contract options for funding a rooftop solar system.
Traditional Financing
Traditionally, a business interested in making a capital acquisition would apply for a commercial loan or line of credit from a bank. In the current economic climate, however, it often proves difficult, at best, to obtain such a facility. For this reason, certain integrators and industry trade associations have recently established financing programs to assist with the acquisition and installation costs. Some banks have also dedicated millions of dollars to financing programs that offer debt and tax equity for investment in renewable energy projects.
Operating (Solar) Lease
While classified as a lease, this structure affords a business an opportunity to take advantage of a solar system without incurring the significant initial capital outlay. Typically, a manufacturer of solar systems sells its products to a financing company that in turn leases the system to the end user. The end user is afforded a reduced and fixed utility bill but must assign any tax credits and/or rebates to the finance company or its investors. Often, the leases have long terms and strict conditions and penalties for early termination.
Power Purchase Agreement (PPA)
A PPA enables a business to enter into long-term contracts to acquire electricity produced by the solar system. Typically, the end user purchases the power on a kilowatt-per-hour basis from the energy company and/or dealer of the solar system. It allows for a direct benefit to the business in lower utility rates, while eliminating any uncertainty about the intermittency of solar power. The end user must assign any tax credits and/or rebates to the energy company and/or dealer, or their investors. Often, the PPAs have long terms and strict conditions and penalties for early termination.
Rooftops Can Generate Income
Many commercial, industrial and retail buildings can provide the real estate needed for these systems, and are subsequently viewed as excellent candidates for roof rental.
A growing number of third-party solar power providers are looking to rent roof surfaces from building owners in a designated area, install PV systems and sell the power generated to the local utility companies through pre-negotiated agreements. Building owners don’t have to get involved in marketing the power generated on their roofs, and the lease agreements frequently guarantee at least 20 years of dependable rental income.
Is the Structure Suitable for a PV Array?
Not every rooftop will be suitable for a rooftop installation and some are more suitable than others. The suitability will impact directly on what income one might be offered for the rooftop. In addition to being flat and relatively free of obstructions, the ideal rooftop needs to be exposed to the sun (not shaded by other structures or potential future structures on the building site or on neighboring properties) and physically capable of supporting the weight of a PV array. Size also matters, with the ideal size for a solar PV rooftop installation being in the range of 30,000 to 100,000 square feet.
A new or recently rebuilt roof is preferred, because it is less likely to require additional structural support to accommodate the array, and because it will probably not require significant repair or replacement during the operating period of the solar project, which might necessitate the temporary removal or relocation of the solar array.
Understanding Lease Agreements
Many rooftop rental agreements can look lucrative at first glance. There are, however, several important facts that building owners must be aware of before signing on the dotted line and making a multi-decade commitment. Ignoring these realities could turn a potential cash cow into a fire-breathing dragon that could do serious damage to the bottom line. One of the first questions the tenant will want to know is if the owner has full legal control over the rooftop. That is, the rooftop must not be subject to existing leases to tenants or other legal restrictions, which may prevent the landlord from being able to grant exclusive rights to the operator.
The first thing building owners need to be aware of is that most roof-mounted PV systems can easily last up to 40 years, while the commercial roofing systems they are attached to typically have life spans of between 10 and 13 years. With a 20-year roof rental in place for a PV system, it’s highly likely that roof repairs — or even replacement — will be needed at some point over the course of the rental period.
While a roof lease can provide secondary monthly income from space that previously generated no income or was even classified as a liability, the attractiveness of the deal can disappear quickly if roof maintenance is not factored into the lease agreement. Any failure in the roof surface that causes leaks can disrupt day-to-day operations, drive away customers and do serious damage to the financial stability of a business. Fixing the problems with the roof surface once a PV system is in place will also take much longer and cost much more than a typical roof repair. If it takes days or weeks to fix a leaking roof surface, any financial benefits generated by the roof rental can quickly be replaced with enormous losses that could potentially eliminate several years of rental income. As a result, in any rooftop lease agreement, one needs to know who is going to pay if roof repairs are needed, especially if PV system removal is required. In simple terms, if maintenance is not an integral part of the lease agreement, roof rental is not likely to be a lucrative deal in the long run.
Before involving in a rooftop rental agreement for a solar PV system, the following four facts should be kept in mind:
• Rooftop rental can provide with extra income each month, but can also open up to significant liabilities.
• The building, the roofing systems and the operations conducted in your facility are your primary concerns, not the PV system.
• Maintenance and troubleshooting must be part of any comprehensive rooftop lease agreement.
• Know who is financially responsible for repairs and lost production so you don’t end up holding the bag for costs and penalties.
Without a doubt, an FIT can be an excellent way to put the unused roof space to good use and to collect rent at the same time. By reviewing lease agreements carefully, one can benefit from green solar power generation while knowing that all your financial bases are covered.
The following are some of the typical clauses one might see in a solar rooftop leasing agreement – and the issues to consider.
Option Agreement
Most rooftop solar developers require an option to lease the rooftop. The option will permit the operator to have access to inspect and test the rooftop and do such other investigations as it deems necessary to satisfy itself that the location is suitable for a solar PV array and that the building owner is in a position to grant a lease to it. The option will be open for exercise by the operator for a period sufficient to enable the operator to conduct such inspections and investigations and to apply for and obtain a Feed in Tariff (“FIT”) program approval or enter into a power purchase agreement (“PPA”) with the local electrical utility. The option agreement will provide that if the developer exercises its option, the parties will enter into a lease of the rooftop area on the terms set out in the option agreement.
Tenant Covenant
As with any lease, it is advisable for the landlord to consider the financial strength and “track record” of the tenant, and to determine whether a deposit or other form of financial security should be sought to protect the landlord from the consequences of a tenant default.
Term and Rent
Renewal rights are potentially important, as it is anticipated that the productive life of the solar photovoltaic (“PV”) array equipment may be substantially longer than 20 years. Rent can be structured in several ways. Usually, it will be a fixed, all-inclusive “gross” rent, but it may be calculated based on the size of the roof area or the portion of the rooftop utilized, the wattage produced by the facility, a percentage of the revenues received by the tenant, or on some other basis. In addition, the lease may provide for the tenant to pay for its electricity consumption and for any realty taxes associated with the solar PV array. As mentioned above –payment is received can also affect the rate– this way it qualifies for bank financing.
Access
The tenant will require access 24/7 to install, clean, maintain, repair and replace its equipment – and issues of security access may need to be addressed in the lease depending if the access has to be from within the building or not.
Roof Repair
The lease will need to address the necessity for installation, roof repairs and replacement. Issues such as notice to the tenant, the period to do the work, relocation of the solar PV equipment while the repairs or replacement are undertaken, and compensation to the tenant for lost revenue during repair/replacement will be of concern.
Plans and Specifications
The landlord will want approval rights over the tenant’s plans and specification for the original installation and for any subsequent alterations, repairs and replacements. The tenant will want to ensure that such approval is not unreasonably withheld or delayed.
Ownership
It will be critically important to the tenant, for financing purposes, that its facilities are never treated as building fixtures (i.e. they will not be part of the building and therefore will not be the landlord’s property) but instead are always the sole property of the tenant.
The tenant will also require that the landlord waive any rights of distress or other rights to claim a lien or other interest in the tenant’s equipment, in order to facilitate such tenant financing.
The issue of ownership and transfer of title to the installation (e.g., at the termination of the lease if not renewed) is also important at the term of the lease specifically, if the installation is no longer economically viable or if there are materials containing toxic materials (such as solar panels that contain cadmium or other materials that or might be deemed toxic materials in certain locations).
Financing
In order to obtain financing for its equipment, the tenant may need to assign the lease as collateral security to its lender, and will need the landlord to agree to enter into an agreement with the tenant’s lender enabling the lender to cure any default by the tenant under the lease and to obtain a new lease on the same terms if the lease is terminated without the lender’s consent. The landlord will want the lender to agree that any monetary or other curable default must be cured prior to the new lease being granted.
Insurance
The landlord will want the tenant to obtain and maintain insurance on its facilities, and adequate liability insurance, and the tenant will similarly want the landlord to obtain and maintain insurance on its building as well as public liability insurance. Appropriate releases, waivers and indemnities will also be important to both parties.
Interference
As noted above, it will be extremely important to the tenant that nothing happens that blocks or otherwise interferes with sunlight reaching its solar PV array. Consequently, it will require covenants from the landlord that it will not take or permit any action, which would have such effect. In addition to the normal termination for damage and destruction provisions found in a typical lease, if at some point something happens (such as the construction of a building in the vicinity) that impairs the availability of sunlight or otherwise prevents the tenant from operating its facility, the lease will need to address the tenant’s rights to terminate the lease in such circumstances.
Non-Disturbance
As would be the case for any lease, the tenant may require that the landlord obtain agreements from each of its mortgage lenders to the effect that the lender will permit the tenant to remain in possession of the leased rooftop, etc. notwithstanding any default by the landlord under the mortgage, and will agree to recognize the lease and the tenant’s rights.
Repair and Maintenance
Each party will want to ensure that proper repair and maintenance obligations are included in the lease.
The landlord will want the tenant to properly maintain and repair its equipment to ensure it is kept safe and in compliance with laws and regulations, and the tenant will want the landlord to take adequate care of the building, especially the roof, to avoid any impairment of the tenant’s ability to properly operate its solar facility. Regular cleaning of the panels including snow removal, and disposal may also need to be addressed depending on the location of the building and normal weather patterns.
Solar leasing is possibly the most effective business model for homeowners interested in rooftop solar systems: They can ensure a hefty upfront cost for a monthly fee that takes care of installation and maintenance and quickly start saving money on monthly electricity costs, too. The above demonstrates a variety of options for businesses to use when analyzing the costs and benefits of solar technology. There is no better time than now to lighten up and enjoy the sunshine.
Business Models
Utility ownership
Utility ownership of solar assets is the most direct change in the engagement of utilities with solar markets. For investor-owned utilities, owning a physical asset, solar or otherwise, is how utilities make profits as they earn a regulated rate of return on the capital investment. In contrast, purchasing the solar energy from a third party involves only recovering the costs of the purchase from ratepayers. However, some utilities are beginning to explore, have announced plans for, and are implementing owning and operating solar projects directly. Ownership is most prevalent among investor-owned utilities due to tax incentive structures. As municipal, cooperative and other public power utilities cannot utilize tax credits or depreciation directly and relative to third-party ownership, ratepayers would pay increased costs in this instance. There are a number of positive and negative drivers for this recent trend.
Positive drivers
• Earning a regulated rate of return on owning the capital asset
• ‘Imputed debt’ from power purchase agreements, which may negatively impact a utility’s financial balance sheets
• Decreases in solar costs making it a more reasonable investment option
• Different and available tax equity sources than are prevalent in third-party financing models
• Lower costs of capital for financing relative to some third-party options
• Potential to capture value from tax benefits that might otherwise be lost through ‘flip’ structures that transfer ownership from non-utility investors to utilities after tax benefits have been utilized.
Negative drivers
• Requires approval from regulators; potential negative stakeholder reactions
• Regulatory changes to allow nonphysical assets, such as energy purchases or financing, to be treated as equivalent to capital investments eligible to earn a return
• For certain utilities, lack of tax appetite to utilize tax credits
• Utility or regulator assessments that discourage ownership because of real or perceived technology, performance or other risks.
Utility ownership represents a significant change to the solar industry. Upstream companies likely view this as a new and expanding market opportunity and may welcome the change. However, downstream companies may perceive a threat to their existing ownership business models. Utilities need to anticipate and structure business model design to manage ‘blowback’ issues that could arise. The few utility commission proceedings on utility ownership that have been completed have brought up cost and rate impacts, as well as anticompetitive or monopoly concerns from various stakeholders. Commissions need to ensure that competition remains open and fair, but also that utility ownership serves the economic interests of ratepayers, where third-party ownership could be a lower-cost option. Ensuring competitive utility pricing relative to third-party projects can actually effect downward price pressure on both sectors, which is a win for ratepayers regardless of ownership.
Utility energy purchases & financing
Both energy purchases and financing business models have generally been met with less concern from stakeholders, perhaps because the models are more likely to involve direct partnerships with customers or solar companies, but also because they are less numerous. Although less numerous, the models are increasingly diverse, as outlined in the points below.
• Community net metering or tariff projects, where the utility develops a larger-sized system and essentially sells ‘shares’ in the project that allow customers to offset their consumption directly or pay a fixed-priced tariff based on the output of their share
• Feed-in tariffs that are based on timeof- use or market rates, or that offer more compelling business opportunities relative to a traditional rebate program
• A flip-model between the utility, an investment bank, and site owners; ownership is transferred to the utility after the tax benefits are fully utilized
• Project financing for residential and commercial net metering customers that uses renewable energy credits to repay the loan, and earns the utility a return on its loan investment
• Competitive bidding or auctions for third-party-owned projects that are sited in strategically valuable locations for grid support, smart grid testing, or peak generation benefits.
Trends in Rooftop Solar
- Suniva powering India’s first 1MW rooftop solar plant:
A U.S. manufacturer of high-efficiency mono-crystalline silicon solar cells, modules and high-performance solar cells- is powering India’s first 1MW rooftop solar plant. Implemented and commissioned by Reliance Industries Ltd. (RIL) Solar Group, the 1MW solar plant was built on the rooftop of Thyagaraj Stadium in New Delhi. With the solar plant being located on the rooftop of Thyagaraj Stadium, the overall footprint of the plant is minimized, while ensuring that it would generate enough energy to fulfill the stadium’s requirements of a 1MW plant needed in the rooftop space available. Incorporating Suniva’s high-efficiency ARTisun® series solar cells in RIL modules, the Thyagaraj power plant was developed using a total of 3,640 280Wp modules. The project is expected to generate around 1.4 million kWh of electricity per year to fulfill the power requirements of the stadium, with surplus electricity being fed into the grid at 11KV. The solar power generated from this project is expected to result in emissions reduction of more than 2,640,000 lbs. of CO2 per year. The Thyagaraj Stadium, developed by the Government of Delhi, was a model green stadium and hosted Netball in the recent Commonwealth Games.
- Moser Baer to set up one of India's largest rooftop solar PV installations in Surat:
Moser Baer Photovoltaic (MBPV) has bagged a rooftop solar power installation contract from Roads and Buildings Department of Gujarat to set up one of India's largest roof-top solar photovoltaic installations in Surat, Gujarat. This Solar PV system of approximately 135 KW (peak) capacity will bear a load a 40kW for 10 hours everyday by storing the charge in a battery bank of 6,000 AH (Ampere Hours). This is enough of power to light up a typical Indian village. The project has already started and the complete system will be commissioned by April 2009. Moser Baer PV will manage the operations and maintenance of this installation for seven years. Commenting on the development, Rajiv Arya, the Chief Executive Officer of MBPV, said: "This contract underlines our unmatched capability to design and build reliable and customized solar systems in a cost-effective manner. This project is in line with the Gujarat government's focus on clean and renewable energy in the state." Moser Baer is investing hugely into solar energy harvesting area. The results of its efforts have started bearing fruits.
· Indian State of Gujarat to bring out Solar Rooftop Policy soon: The state government of Gujarat is planning to introduce roof top solar power generation plan in Ahmedabad and other cities like Gandhinagar, Surat, Rajkot, Vadodara etc., on the line of developed countries. In developed countries the concept has got wider popularity. Under this plan they encourage private residential, commercial and industrial property owners to put small solar power generation plants on their building roofs. The electricity generated on roof will be transferred to the various grids. Government shall sign MOU(memorandum of understanding) with AEC and other power supply companies for buying solar power. Private roof top solar technology companies will invest and install roof top solar installations in cities on private properties and generate solar power.
Some Myths and Facts:
India has abundant sunlight, but it has yet to tap this clean and green source of energy for power generation. The advantages of using this source will reduce our dependence on fossil fuels. India is blessed with abundant sunlight, averaging approximately 300 sunny days in a year. India has yet to utilize this advantage in terms of power generation. The country is still heavily dependent on fossil fuels, which are unviable in the long run. The highest proportion of installed electric energy comes from coal, which is polluting and a non-renewable source. Also remote areas and villages where Grid supply is not available, Solar Off Grid installation makes lot of sense. Certain myths are created around solar energy, which need to be broken before one could clearly identify it as the only beneficiary in long term.
Myth 1: Solar energy generation is only possible at places with abundance of sunshine.
The fact: Sun's energy is the most evenly spread source of energy in the world. Where there is light, solar panels will work. The worlds largest market for solar energy is Germany, a country not particularly blessed with long sun filled days but it has largest solar installation of the world, just because of smart governance! In the summer, almost 10% of the household electricity in the south of Germany is generated by solar panels. Of course, when developing systems in barren lands having lot of sunshine like Thar desert, the return on investment (ROI) will be higher. But many other factors
come into play, such as the presence of a grid, the local consumer price for electricity, the energy usage pattern, policies and much more. As an example,in North Eastern part of the country, it is smarter to invest in solar energy than to pull a cable from a faraway power plant or grid connection point.
come into play, such as the presence of a grid, the local consumer price for electricity, the energy usage pattern, policies and much more. As an example,in North Eastern part of the country, it is smarter to invest in solar energy than to pull a cable from a faraway power plant or grid connection point.
Myth 2: Solar energy is costly and needs government subsidy to become competitive!
The fact: People will never buy laptops. Flat screen televisions are too expensive for the general consumer market. Mobile communication is too expensive in comparison with landlines. These are some of the opinions that we have heard in the past - and how untrue they are, isnt it? Laptops, flat screen televisions and mobile phones are now everywhere, because people wanted them and were willing to pay for them - with the result that in the end prices fell due to mass production that could be applied for these innovative products. The same is now happening with solar energy systems. In the past three years, the prices of solar panels have dropped by half, as a result of the introduction of large scale
production methods. We believe that by 2013-14,solar energy cost of production will match the electricity produced from thermal and other conventional energy plants. Public funding was created in the past to accelerate this process of acceptance by the general consumer. In the largest markets, subsidies are now in the process of being terminated.
production methods. We believe that by 2013-14,solar energy cost of production will match the electricity produced from thermal and other conventional energy plants. Public funding was created in the past to accelerate this process of acceptance by the general consumer. In the largest markets, subsidies are now in the process of being terminated.
Myth 3: Efficiency of solar panels is still too low.
The fact: What is at stake now is not the efficiency of panels, but the price per generated kilowatt-hour. Just as it is no longer about the type of engine in a car, but rather about how much fuel the motor consumes per mile. There will still be new types of solar panels developed, with improved efficiency, but
the real success of solar energy in the future will lie in large scale production and the growth of the global market.
the real success of solar energy in the future will lie in large scale production and the growth of the global market.
Myth 4: Since they cannot work in cloudy condition or night, they are unreliable!
The fact: It is wrongly perceived. Solar module comes with 25 years warranty, which is unparalleled because there are no moving parts and hardly require maintenance. Right now, the wind energy market is (still) bigger than the solar energy market, although the sun is a more reliable source of energy than the wind. But solar energy will soon surpass wind energy firstly because solar panels can be used anywhere and secondly because they can be implemented in a modular way. This means that it is very easy to expand the solar energy system over the course of months or years. So it makes solar
option very reliable system.
option very reliable system.
Myth 5: Solar panels take lot of space.
The fact: This really depends on personal taste. Of course, there will always be people who believe a smoking chimney of a coal power plant is the best industrial technology and aesthetics. Other people
don’t mind showing that they are generating their own electricity and therefore have solar panels on their roofs. Anyway, there will always be enough space on earth for all the solar panels ever needed. Only a relatively small barren area of 200 kilometers installed with today's solar panel technology would be needed to fulfill India’s entire electricity requirements.
don’t mind showing that they are generating their own electricity and therefore have solar panels on their roofs. Anyway, there will always be enough space on earth for all the solar panels ever needed. Only a relatively small barren area of 200 kilometers installed with today's solar panel technology would be needed to fulfill India’s entire electricity requirements.
FAQs
A typical example for the size of a solar system at home?
Typically a two-bedroom apartment with 3-4 people will consume approximately eight units of power per day. In case, the supply system for only 4-6 hours a day has to be supported,1 KW solar system will be sufficient.
What is the expected cost of 1 KW system?
Actually, many factors play a vital role in the costing. However, considering subsidy up to 30%,a system should cost in the range of Rs.1.2 to Rs.1.5 lakhs.
What is the best advice for a customer?
Best advice would be to use energy efficient products first and then go for the solar roof top systems. Every house normally has enough roof top area to install solar power systems. The life of solar panels is guaranteed for 25 years and good quality solar batteries also last for approximately 7-8 years. Hence, if system is installed by qualified system integrators, the chances of a trouble free system with least attention, is very high. If compared with a normal inverter which does not have any pay back, solar power packs are the best option.
How does compare it with DG sets ?
The cost of power generated by DG set comes over Rs.20 per unit. The maintenance cost, storage problems, pilferage of diesel, space requirement, need of an operator, etc., add up to the cost substantially. Whereas, a solar PV gives uninterrupted, trouble free service for number of years. As
explained earlier, considering the subsidy reduces the payback period of a
solar system to less than 3.5 years.
explained earlier, considering the subsidy reduces the payback period of a
solar system to less than 3.5 years.
What are the disadvantages ?
1. Lack of knowledge about the system and the Government policies like subsidies, concessional loans, accelerated depreciation and RECs
2. Very few qualified system integrators
3. Distracting CAPEX
4.Low reliability factor due to solar irradiation (cloudy days)
5.Space Requirement
What are the incentives by the government?
For the individual house holds, upto 1 KW and for Associations, Corporations, Industries, etc.,. upto 100 KW for each location, the subsidy may be upto 30 %. In case, either the location is different for the same user or the owners of the projects are different for the same location, the project(s) qualifies for the subsidy as per above limitations. It is also important to note that for availing the subsidy, prior approval of the project by MNRE is must.
What are the challenges in the design of solar PV system?
Typical mindset of the customer is that they start comparing Solar system with other Backup power system like DG set on one to one basis. One has to keep in mind that raw material for producing power from solar system is free! The other challenge is the design of the system which handles variable flow rates using induction motors like in petrol pumps or process chemical industries. In the congested multistoried complexes the space also becomes a big constraint. Lack of knowledge about the systems.
