How much electricity does a solar panel produce electricity bill bihar electricity board


If you look closely at the solar panel in the image above, you’ll notice 60 little squares. These squares are actually individual solar “cells,” which are linked together by wires. The cells are where electricity is made, and the wires carry the electricity to a junction box where the panel is hooked into a larger array. Why does solar panel size matter?

To determine an STC rating, solar labs test the panels under ideal conditions called “peak sun,” or 1000 watts of sunlight per square meter of surface. That’s approximately equal to the power of the sun at noon, on a sunny day, at the equator.

In the picture above, the label shows an STC rating of 250 watts for the panel. If that panel received full sun for one hour, you’d get 250 watt-hours of electricity. With 4 panels, you’d get a kilowatt hour. Click here to read more about the difference between a kilowatt and a kilowatt hour. Solar panel output calculator (kWh)

Even if you live at or near the equator, you can’t expect to replicate these ideal conditions. The amount of electricity solar panels produce depends on average sunlight over the course of a year. If it’s historically more cloudy in your area, there’s less available energy from the sun to convert into electricity.

The first step to figuring out how much electricity your solar panel can produce in a year is to find your place on the globe. If you live in the United States, you can figure out how to calculate the amount of electricity a solar panel produces and how much you can save using our simple solar calculator:

If you live outside the United States, check out Weather Underground’s solar calculator. You can enter your address into it and get specific details about how much sunlight hits your house on average. The calculator also gives the option of entering a specific model of solar panel and the square footage of the panel coverage on your roof. Solar panel output per day and per month

Using the example above of a 250-watt STC rated panel, if you multiply the 250 watts the panel produces by the number of hours of full sun you get in a day, you’ll get the amount of kwh that panel produces per day. Multiply by 30 days and you’ll get mothly kWh output for the panel.

The average roof in the United States gets about 4 hours of usable sun per day. We know the sun shines more than 4 hours, but “full sun” is a measurement that combines all the parts of the day when the sun is lower in the sky into one number.

Typically, homeowners in the United States use about 900 kWh a month on average. So, take 900 kWh and divide by the amount of kWh one solar panel produces over the course of a month (30kWh), and you get a 30 panel installation. 30 panels x 250 watts per panel equals a 7,500 watt system (7.5kW).

Again though, these are just rough estimates. It’s best to connect with an expert we trust near you who can appropriately size a system and help take advantage of all the local incentives to get it done right and as affordably as possible. How much power do my devices use?

There’s huge variation in power use between households depending on what you own and how often you use everything. People in the South and West United States tend to use more electricity for heating and air conditioning, whereas people in the North and East tend to heat with gas or fuel oil.

One basic old-fashioned lightbulb uses 60 watts of electricity; a CFL uses 18 watts. Laptops often use about 45 watts, and desktops can run between 150-300 watts. Window air conditioning can range between 500 and 1500 watts, and central air conditioning can use 3500 watts.

The average home in the US uses about 1,000 kWh of electricity per month. All those little devices add up to big usage, with variations by season. Usage also varies between day and night. Unless you work at home, most of your electricity usage probably happens at night. On or off the grid?

If your solar panels are producing more energy than you’re using—when you’re at work, on vacation, or just not running many devices—excess power will flow back into the grid. In many locations, utility companies offer a program called “ net metering” that can compensate you for extra power you produce.

At night, or anytime you need extra power, you’ll pull it from the grid. With a grid-connected system, you’ll never need to worry if you happen to need more power than your solar system has been sized to provide. You may also choose to supply only part of your average electricity bill with solar, and use the grid for the rest.

So from the calculator above, you can see 11.1 kilowatts (kW) of panels can fit on your 1,000 square-foot roof. That 11.1 kW is called the panel rating, and it represents the amount of power the panels can generate in full sun. The next part of the calculation is to take that 11.1 kW and multiply it by the map’s number for your area (1,500). 1,500 is the total number of kilowatt-hours (kWh) generated per kW of panel rating per year.

So 1,500*11.1=16,650 kWh per year. But that number represents an ideal environment, and lots of things change how much of that power becomes usable. Electricity loss from wiring, DC-to-AC inversion, heat, cold, wet, etc can affect how the panels produce, so we usually assume about 20% of that ideal generation will be lost.

Divide that number by 365 days, and you get about 36.5 kWh per day, on average. Obviously, sunny days in summertime will lead to more generation, and cloudy, rainy, snowy days will lead to less, but the average will be about 36.5 kWh, or about 75% of your 49 kWh average.

You are probably right at where you want to be. Assuming a 30 day month, you are using a little under 12 kilowatt/hours per day. (Congratulations by the way on minimizing your electricity demand!) A 3 kilowatt system will probably produce an average of about 15 kilowatt/hours per day. Obviously that will vary depending on if you are in Maine of Texas, but it’s a good rule of thumb. There will be some losses along the way from the inverter, wiring and so on so a 20% overproduction is about right. If you are in a northern state you might want to bump it up a bit if your goal is to produce 100% of your electricity, but here’s the thing: You can always add a few more panels. Having extra electricity production only makes sense if you are currently unhappy with the lifestyle that has gotten your usage so low, and you would welcome the opportunity to use a bit more electricity. For example, if you would like to add a window air conditioner, you would probably welcome a bit of extra electricity flowing through your wiring!

There are a couple of possible issues. It’s unlikely to be a problem with the panel, they are pretty foolproof, but it wouldn’t hurt to test the output and see if you are getting the amps you think you are. It’s more likely to be an issue with the battery. Batteries start with a ~95% efficiency but that can fall to 50% depending on the battery’s age and the usage. If I had to guess, based on the information provided, I would guess your battery has some sulfur from the sulfuric acid bonded to the battery plates, and that’s reducing the efficiency of the battery. You can buy a Battery Tender pretty cheaply online and hook the battery up until the light glows green and pulses. This may take a few days, depending on the condition of the battery. After that, you can use the Battery Tender periodically to maintain the battery. It’s possible the battery is too far gone, and you may need a new battery, if that’s the case, use the Battery Tender as often as you conveniently can to avoid damaging your new battery. In general, the best way to keep your battery happy is to keep it as charged as possible and to drain it as little as possible before recharging it. I hope that helps!