A: Based on industry in-field experience, laboratory test results and reliability testing, PV modules will last longer than 30 years in service provided proper care and regular maintenance are effective. However, manufacturer's warranty is generally given as 100% efficiency for 20 years, and at 80% efficiency for the next 5 years, totalling about 25 years performance warranty. But expected useful life of solar panels will be definitely 30+ years. Module failure rates are estimated at less than 1% over its whole life cycle.
2. Is solar electricity produced in bright sunny days only?
A: No. The best weather for producing solar power is surely the sunny day. This does not mean that solar electricity can be generated during sunny days only. Solar panels do produce electricity in cloudy weather. They don't produce as much electricity as they do on sunny days, but they have been shown to produce 25% of what they produce on a sunny day or 10% when it's very cloudy.
3. If I install a Solar PV System at my place, how much working Life Span can I expect from it?
A: Most home/small office solar power systems have a lifespan of between 25 and 30 years. Usually solar manufacturers guarantee that after 25 years of operation solar panels installed will generate about 80 % of the electricity they generated after system launch.
4. How much Roof Top Area do I require to install a Solar PV System?
A: First of all the required roof space depends on your daily electricity needs. Obviously the more energy to be generated, the larger roof area needed. What also matters is the number of bright sunny days in your area i.e. it is mandatory for a Solar PV Setup to have a shade free area all the time of the day. The most important factor on which the area of a Solar PV System depends is the Panel Efficiency. Generally, a Solar Panel with 15% efficiency requires 100 Sq. Ft. of shade free roof area. While a Panel with 12% efficiency needs approximately 125 Sq. Ft. of shade free roof area. Another factor is the weight of the Solar Panels that may put pressure on the roof of the building. For very old and poorly built buildings the Panels have to be scattered in a larger area so that the construction can withstand there weights.
5. A photovoltaic system of what size do I need?
A: The size of a solar system depends on how much electricity you need daily. Furthermore the size is restricted by your roof area and available budget. The size of the system is usually directly proportional to the amount of power you use.
6. Do I need batteries?
A: Is back-up power critical to your business? If YES then you need back-up batteries. For most businesses, the answer is "no" and if you don't have a back-up solution today, an ordinary grid-connected PV system will leave you in the same position
7. What if a solar panel gets struck by a lightning?
If you buy a solar system from a certified vendor/installer, you can be sure that it is designed to withstand lightning. In case of a solar panel hit by a lightning, your solar vendor is fully responsible for all the subsequent repair works.
8. Do solar panels need to be tilted at an angle?
A: Ideally yes. To achieve maximum performance of your solar system, solar panels need to be tilted at a certain angle. Moreover different tilts are recommended to optimize solar system performance in summer, in winter and all the year round. It should be noted however that for system performance tilt angle is less critical than orientation.
9. What roof type is best suited for a solar system?
A: The roofs suitable for installing solar panels should:
Be unshaded, atleast between 9 a.m. and 3 a.m. every day
Have easy access to and be not too steep
Have enough free space for panel installation
Be made of composite.
If your roof is not having any shade from adjacent buildings, trees etc and its structure is not delicate then your roof is suitable for installation of solar plant. Solar plant can also be installed on car parks, open shade ground within your premises by erecting special mounting structures.
10. How many solar panels do I need?
A: The area needed to install solar panels depends on:
Your energy needs, i.e your daily energy target
Available solar energy at your location
Type of solar panels used (that is, solar panels efficiency)
The number of solar panels depends on the needed area and on panel size. You can easily get the number of panels required by dividing the area by the typical panel size which is 16 square feet (or 1.5 square meters).
11. Can I add solar panels to my home solar power system later?
A: Yes, but that might be complicated because your system needs to be resized. This means that you will probably have to replace some (or all) of the main components – inverter, charge controller and battery bank. A smart idea would be to oversize your system a bit in the process of initial evaluation – that is, set your daily electricity target somewhat (you choose how much exactly) higher that your real consumption by considering your increasing needs for electricity in the next few years. Mind however that there’s not such a thing as ‘free lunch’ – for oversizing you have to pay extra money which obviously will not match your energy needs at the moment of system start.
12. Will my solar system keep on generating electricity if the utility power goes out?
A: No. If you have a solar system connected to the grid, in case of a power blackout your system will shut down immediately until the utility supply is restored. This feature is provided for safety reasons and is a must for every grid-tied system.
Should such a grid power outage be unacceptable for your home or office, you could consider buying and installing a grid-tied system with power backup.
13. What kind of maintenance schedule do I have to follow to keep the Solar PV System in a healthy Condition?
A: As a rule solar electric system need little maintenance since they do not have any moving parts. During solar system lifespan (which is expected to last between 25 and 30 years) the following components have to be replaced:
Inverter and/or charge controller (if any) – every 10-15 years of operation
Batteries – every 5 years of operation.
14. How frequently should I clean my solar panels?
A: As a rule you don’t need to regularly clean your solar panels because it’s not necessary. Yes, solar panels do get soiled by dust, bird droppings, etc. but wind and rainfall act as natural cleaners, so that generated electricity remains near its optimum. You have to clean your panels upon a heavier drop in electricity production (10-15%) occurring in very special situations, such as a forest fire in your area.
15. We don't own the property on/in which we operate. Can we still go solar?
A: Yes, it's relatively commonplace for property owners to allow their tenants to make improvements in their facilities and we have many customers who are tenants with long-term leases.
16. How long will my installation take?
A: This depends mostly on the size of the system, site access, and the distance between the array(s) and the main electrical service. In general, figure one week for each two hundred modules to be installed.
17. What parts will break first?
A: The inverter(s), which typically have a useful life of 15-20 years, will be the first thing to fail.
18. What about rust and oxidization?
A: All hardware is made for outdoor use and is made of either rust-proof stainless or galvanized steel, aluminium or high-grade outdoor-rated plastic.
19. Do Solar Panels Need a Lot of Maintenance?
A: Typically solar panels require very little maintenance. If rain doesn’t do the job, you can spray them with a hose a few times per year. You should make sure that there is nothing piled up on top of the solar panels which could block them from the sun. Ideally you should check with your installer about maintenance requirements.
20. Do solar panels work with artificial light?
A: Yes, solar panels will work under artificial light but not as efficiently. One concept that is worth considering regarding this matter between solar panels and artificial light is a fundamental law of physics. Whenever energy is changed from one form to another, what results is a net loss. It is highly recommended that you just stick with sunlight to power your solar panels.
21. Will my solar panels work if there is a power outage?
A: With a on-grid system is connected to the utility company) power will be lost, however you can switch to a backup generator for electricity. If it is an off-grid system with a battery bank to store excess created energy, then you won’t experience the blackout as long as the electricity supply is not depleted.
22. How much electricity does a rooftop solar PV system generate?
A: The amount of electricity generated by a rooftop solar PV plant depends on the location, orientation of the roof, panel efficiency, and ambient temperature. As a rule of thumb, a 1 kWp plant will generate about 4 kWh (units) of electricity a day on average in a year.
23. How do Solar Panels produce electricity?
A: Solar Panels work on the phenomenon called the Photoelectric Effect to produce electricity. Solar Panels are nothing but blocks of specially designed semiconducting material which produce a small amount of electricity when light falls on them. This small amount of electricity is produced in a large number of solar panels (Solar Arrays) to produce electricity for everyday consumption.
24. What is the difference between an off-grid and on-grid solar roof top kit?
A: On-grid means your solar system is tied to your local utility company’s system. This is what most residential homes will use because you are covered if your solar system under or over-produces in regard to your varying energy needs. In in grid plant, there is not any battery system, the solar PV plant is connected to the grid from where the AC power comes.
Being off-grid means you are not connected in any way to your grid’s power system or utility company. This is appealing because you are 100% self-sustaining your energy use. In off grid plant, there is a battery backup, the surplus energy get stored in the batteries and that energy is consumed later.
25. What is Net Metering? How can I be benefited from it?
A: Net Metering is a policy that allows the unused power produced by the Solar PV System to be fed to the Grid to which the system is tied to. This allows the system owner to get concessions on his electricity bills as the amount for units fed to the grid will be deducted from the amount of units actually consumed by the owner and the billing will only be done for that part of the units.