Calculate what size solar power system you need for your home

Calculate what size solar power system you need for your home

Powered with technology from

How much will the right solar power system cost for your home?

Written by Chris Meehan

Updated August 13, 2021

5 minutes read

Categories: Solar 101, Solar panels, Solar power, Solar batteries storage

Choosing the right solar power system for your home

Answering this question involves working out what size of solar power system you need and what type of solar power system you want. 

The solar system cost calculator above calculates the cost of a standard grid-connect solar power system from your home. It takes into account the size of your power bill and your location to tell you how many solar panels you need.

It then shows how much the installed solar power system will cost based on the current prices charged by solar companies near you, less any applicable solar tax credits or other incentives.

It uses machine-learned artificial intelligence to ensure the solar panels will fit on your roof and to suggest the best place for them.

It is extremely accurate given how little information it requires.

What are the different types of home solar panel system?

  • Grid-connected solar systems;
  • Hybrid solar systems; and
  • Off-grid solar systems.

What is a grid-tied solar power system?

The most common type of solar energy system for homes are grid-connected (or grid-tied) solar systems. These systems are simply solar panels on your roof and an inverter to convert the DC power made by the solar panels to AC power (the type of power your home uses). The system is connected to the utility company grid through your meter box and a special solar meter.

Solar power system infograph


What is a hybrid solar system?

A hybrid solar system is a grid-tied solar system that also has a solar battery for energy storage. These can give the best of both worlds because you can store excess energy in a battery for backup power during a blackout, or to use during expensive evening peak electricity pricing hours. The advantage of still having the grid connection is that you don’t need to 100% rely on your solar and battery. This means you can have a smaller and cheaper energy storage system compared to the same home that is completely off the public grid system.

However, solar batteries add a lot of cost to a solar system for home. One of the leading home solar energy storage systems, the Tesla Powerwall has just had a price increase and it is hard to find a financial justification for the Tesla Powerwall cost where you have access to net metering.

Net metering does economically what a solar battery does physically, allowing you to store the economic value of your excess solar energy (kWh or dollar credits) for use at night without the cost of physically storing the electricity. So for 99% of homeowners currently connected to a public grid, a simple grid connect system will be what you want.

Why time-of-use electricity billing may make solar energy storage for solar panels viable?

Time-of-use electricity billing became mandatory for customers of investor-owned utilities in California in 2019. This trend is likely to spread as administrators seek to reduce demand on the electricity grid during peak times.

In 2018, the Tesla Powerwall introduced time-based controls allowing you to charge the battery in off-peak times and use this power later during peak times. This is an added bonus that you get if you have a hybrid system. The economic value of this functionality depends on how big the difference is between on-peak and off-peak electricity rates. If the difference is 10 cents per kWh and the Powerwall home battery can store 13.5 kWh of power, then this is a possible return of $1.35 per day or almost $500 per year.

Whilst this alone doesn’t justify the cost of spending $7,000 on solar battery storage — the Powerwall installed is now around $10,000 but may be eligible for the 26% federal solar tax credit — it might in the future.

How much will a solar power system cost for my home?

You can find home solar panel installation cost on SolarReviews. SolarReviews has data on almost 900,000 residential solar installations and also has current price lists for many of the solar companies near you. To find current solar prices, drill down from the national solar cost data to the data for your city.

As of January 2020, the average cost of solar panels per watt in the US ranges from $2.57 to $3.35/watt. A typical 6 kW solar system (6000 watts) will cost anywhere between $15,420 and $20,100 before the federal solar credit which is equal to 26% of the cost of installing a solar system. This equates to a monthly payment of less than $100. You can use our solar calculator to get cost and savings numbers tailored to your locations and home and this will also get you prices from local solar companies tailored to your home.

Where can I compare prices on solar energy systems?

You can compare prices on solar systems from local solar companies on our site. Once you enter your zip code and monthly energy expense our calculator will work out the size of system you need to cover your power bill and then show the offers available from local and national solar companies on that system.

Where can I find reviews of the solar companies that operate in my city?

You can find reviews of each of the best brands of solar panels to use for your home solar system and the best solar companies near you to install them on SolarReviews. You will find both expert reviews and consumers reviews of solar panels and solar panel installation companies.

What is an off-grid solar power system?

As the name suggests, an off-grid solar power system is a solar panel system that is not connected to a public utility grid. These systems can either power a house where the home is located outside the reach of the grid or it can power things such as boats, caravans, and RVs where mobility is required.

It should be noted that while almost all solar systems in the US can qualify for federal incentive programs like the federal Investment Tax Credit, you’re more likely to get more incentive opportunities, like net metering (allowing you to sell power back to the utility) with a grid-connected system than with an off-grid electric system. This is because most incentives are offered locally through utilities. Local solar installers are the best to contact to see if there are any local city, state or utility incentives available in your area. Most of these incentives are also visible through the solar calculator referred to above.


Author: Chris Meehan

Chris Meehan is a freelance writer for Solar-Estimate. With more than a decade of professional writing experience, Chris focuses on sustainability, renewable energy and outdoor adventure articles.