PV is different that solar thermal technologies (like solar water heaters and solar cookers), where these solar thermal equipment use the heating effect of sunlight. Solar thermal equipment use dark coloured material or specially built ‘evacuated’ collector tubes to absorb sunlight and convert it to heat. That’s how you get hot water or cooked food. On the other hand, PV gives you electricity.

A net-metered PV system is connected to the internal wiring of a home or a building. This way, the electricity generated by the PV system is ‘mixed’ with the electricity taken from the grid. Let us consider a case where a grid connected PV system of 6 kW is connected to a home, which is being net-metered. Now let’s say, that on a cloudy day, the house’s load is 3 kW and the PV system is generating only 2 kW. In such a case, the house will ‘import’ 1 kW from the grid. The consumer will not know which electricity is being used, but the net-meter will record a consumption of 1 kW at that instant. Case 1: Net Consumption Let’s consider another scenario. Say, that on a bring afternoon, the house’s load is again 3 kW, but the PV system is generating 5 kW. In this case, the extra 2 kW will be ‘exported’ to the grid. The net-meter will record this export of 2 kW, and the consumer will get credited for the exported energy. At the end of the billing cycle, the consumer will receive a bill reflecting only the ‘net consumptions’ i.e. total import minus total export. Hence, net-metering is a very simple yet effective mechanism of utilizing solar energy. A net metered PV system is advantageous to the consumer, because one can completely avoid the use of batteries. Batteries are expensive, not very environment friendly, require additional maintenance, reduce the efficiency of the overall PV system, and need to be replaced often. The extra solar electricity is exported into the grid, while at the time of more demand, electricity can be imported from the grid. Hence, the grid ‘behaves’ like a battery.

Yes, you can easily run air-conditioners or equipment with heavy loads along with your netmetered (or any other scheme of grid connected) PV system. To some extent, this questions is addressed in the previous answer. Using the same logic in the previous answer, if the load of the air-conditioner is higher compared to the electricity being generated by the PV system, then the remaining amount of electricity will be supplied by the grid. This way, the PV system will reduce your consumption from the grid.

The performance of a PV system, whether a large megawatt-scale system or a small kilowatt-scale rooftop system, is dependent on nature: particularly, sunlight. Some days, months or years are sunnier than others, and hence, the PV system will generate more electricity. While on a cloudy day, the PV system will generate less electricity. However, fortunately there is ample recorded weather data (radiation, temperature, etc.) over the last several decades using ground-based weather stations and satellites, which allow us to predict the performance of a PV system with a fair amount of accuracy. Moreover, if the output of the PV system is low during a particular year due to lower irradiation or a prolonged monsoon, this deficit might be covered up during the subsequent year.

Capacity Utilization Factor (CUF) reflects the fraction of time the solar PV system would run at full capacity. If a plant ran at full capacity day and night, then the CUF would be around 100%. However, because the solar PV system runs only during the day time, and its peak generation is achieved around noon, its CUF is usually much lower. As the CUF also depends on the sunlight received, it varies from year to year. The CUF indicated here is very realistic, calculated using satellite data gathered over many years, and based on performance of other existing solar plants in your region.

Let us assure you that PV is a very mature and reliable technology. It has been around for several decades. Earlier, it was mainly used in space applications (since 1958, to be precise), but lately it is becoming a popular substitute for conventional electricity as the prices have drastically dropped. PV modules are designed to last 30-35 years, and come with a 25-year performance warrant. This itself is proof of its reliability. As to evolution, it is the nature of technology to evolve, whether it is a mobile, internet, TV or a car! If the technology does not evolve, companies go out of competition. PV is no different. Streetlights often stop working due to other issues, such as improper cleaning and battery maintenance, or even thefts of its components. However, net-metered PV systems have a very good performance track record and one of the most popular ways of deploying solar technology.

This is very important for a consumer to understand. The electricity grid’s safety standards require the grid-connected PV system to shut down if there is ever a grid outage; this is called ‘antiislanding’. The IEC standards that we follow require the grid connected PV inverter to shut down if the grid voltage, frequency or certain other parameters go out of a pre determined ‘safe’ range even for a split second! This way, if a Utility Engineer is doing some maintenance or repairs after shutting down the grid, he will not have to worry about getting a shock if some grid connected PV system is still injecting electricity into the grid. On the down side, the consumer may not be able to utilize the electricity generated from its own PV system when the grid is shut down. This is not a major issue at locations where grid outages are not frequent. However, at places where the grid is unreliable, we offer hybrid PV systems, which use batteries, and will continue supplying power to the consumer by disconnecting the consumer’s house from the grid. However, such hybrid systems are more expensive compared to regular net-metered PV systems.

i. Once MF Square Technology surveys your existing rooftop, studies your electricity bill, and understands your constraints (if any), we will then propose the capacity of your netmetered PV system along with its cost.

ii. You will then sign the installation and service contract with MF Square Technology, after which MF Square Technology will help you fill up GEDA’s application form (required for interconnection, subsidy, etc.), will submit it and start following it up on your behalf.

iii. After scrutiny, once approved, GEDA will inform us of the approval and also forward the same to your Distribution Company and the Chief Electrical Inspector (For systems above10 kW).

iv. MF Square Technology will then submit your PV system drawings and specifications to the Chief Electrical Inspector and get them approved (For systems above 10 kW). 

v. MF Square Technology will submit your application to your Distribution Company for a netmetered connection.

vii. MF Square Technology will then commence and complete the installation of your rooftop PV system.

viii. Once the rooftop PV system is installed, we will intimate GEDA, the Distribution Company and the Chief Electrical Inspector (For systems above 10 kW). for inspection and commissioning of the system.

ix. Once the rooftop PV system is commissioned, it can commence operation and the Distribution Company will automatically start accounting for your solar energy generation and incorporate it in your billing.