Term Definitions

How long will my solar system last?

You can expect your system to last 20 to 25 years.

Will my system need maintenance?

Solar electric systems don’t require much maintenance. There are no moving parts. The first major maintenance required will be when your inverter reaches the end of its lifespan. Depending on equipment type, this will be between 10 and 25 years into the system’s life. If you have a lease or power purchase agreement, this cost will be covered by the maintenance plan. If you own the system (cash or loan), you will pay for the replacement costs yourself.

Do I need to clean the panels?

In most locations, rain and snow will clean your panels for you. If you live some place where dust and leaf debris are a problem, you may get improved energy production by having your panels cleaned yearly.

What happens if I sell my house?

The reduced cost of electricity for the new homeowner should add value to your home sale. The actual value varies by region. For loan purchases, the loan can typically be paid off as part of the sale. If you have a lease or power purchase agreement, the agreement can usually be paid off during the sale or transferred to the new owner. Our Solar Guides can confirm the exact options available for your agreement.

Do I need to replace my roof before I install solar?

If your roof is more than 10 to 12 years old and showing signs of wear, you should consider having it inspected by a roofing professional to determine its remaining lifespan. The solar system installed on your roof will last between 20 and 25 years; during that time it may provide some protection to your roof from the elements, actually extending your roof’s lifespan. Should you need to replace your roof, a solar professional can easily remove the solar system in advance of your roof work and re-install it when the work is complete.

Will my solar system work when the power goes off?

The most common kind of solar PV (“grid-tied”) systems do not work when the power is off. To allow a system to provide energy when the utility power is out, you must also have a battery system. Adding batteries is more costly and less efficient than a simple grid-tied system. For homeowners where utility service is not reliable this may be a good choice. However, most homeowners choose a grid-tied system that is more cost effective and efficient.

If I generate 100% of my power from my solar panels, will I be able to go off the grid?

Depending on your available roof space, you may be able to have a solar PV system that covers all your electricity usage, but you won’t be able to go off the grid. The grid provides you with energy whenever your solar array isn’t producing any energy, like at night for example. Even though you can’t go completely off the grid, installing a battery system can help you prepare for emergency situations by storing energy for power outages. These systems do cost more however, and usually don’t make economic sense for people with reliable utility service.

Does solar work on days when there isn’t much sun?

On cloudy days, solar continues to work, but does produce less energy.

How does solar work with my home electrical system?

The solar energy from your system will enter your home electrical panel (in most cases) and be available for use by your home. If appliances and other electrical loads in your home need energy, they will use the solar energy before pulling additional energy from the utility grid. On days when you make more from your solar system than you need, it will go back to the grid and you will get a credit. On days (and nights) when you use more than you make, you will pull energy from the utility grid. Based on the monthly energy bill estimate you give us, we’ll tell you what percentage of your total electricity usage will come from solar power over the course of a year.

What happens when snow and ice build up on panels? Does it have to be cleared? Am I responsible for that?

Snow and ice will be shed on their own from the modules over time. Because the panels are dark in color, they usually warm up and clear themselves of ice faster than the rest of the roof.

Will I get a Federal and State Tax Credit or Deduction?

If you own the system (cash or loan financing), you will receive the applicable Federal and State tax credits.

How much will this cost? What does it include? Installation, equipment, permits, inspections, anything else?

Costs vary depending on whether you purchase your system in cash, use loan financing or go with a lease or power purchase agreement (where available). Loans, leases and power purchase agreements can cost as little as no money down with monthly payments made for the term of the agreement. With cash, you will pay most or all of the amount to the installer upfront, (usually with milestone payments) and receive some back after you claim any applicable tax credits. In all cases though, what you receive is a turnkey solution that includes all equipment, installation, permits, inspections and project management. In many cases, system monitoring services are also included in the price.

How long is the warranty?

Lease and power purchase agreements
The warranties are handled by the third party company who will maintain the system for the full term of the agreement.

Purchased systems (cash or loan) – There are several different warranties involved:

Workmanship Warranty Provided by the installer. It covers the installation workmanship. Lengths vary by State and provider.
Equipment Warranty Provided by the manufacturer. It covers the manufactured equipment (modules & inverters) from defects. Lengths vary from 5 to 25 years.
Production Warranty Provided by the module manufacturer. It covers how much power loss is expected over the life of the module.

Why does my home not have a color map on it when everyone else’s does?

The color maps are made using a lot of different datasets by an automated process. Automation results incur some percentage of error, including unfortunately some properties being missed. There are several reasons this can happen:

Your home wasn’t there when the data was captured. If your home was constructed after the data we used was captured, your house will not appear on the map.
Certain roof materials and constructions are difficult to perceive, capture, or differentiate – terra cotta roofs look like dirt, roofs with a lot of complex facets can look like trees, etc.
A tree overhangs the building significantly. The shading of the tree prevents the automation from seeing and identifying the building.
Your home is sitting in a place that may be classified as swamp area. Our automation may have removed the homes in your area if the land had been designated a swamp before being developed.
Your home is sitting on a parcel that is classified as vacant, abandoned, a park, etc. by other datasets used to correlate what areas may have properties on them.

Term Definitions

General Terms

PV – Photovoltaics The technology used in solar panels to convert sunlight into electricity

Product Types

Cash You own the system and pay the entire cost up front without any financing. Note that if you decide to purchase a system using a home equity line of credit or some other financing you access yourself, this will still be a “cash” purchase through Geostellar.
Loan You own the system and pay monthly on a loan provided through a Geostellar partner.
Lease A third party owns the system and you pay monthly or up front for its use. Lease availability varies by State.
$0 Down Lease You pay nothing up front and agree to pay a monthly amount for the life of the lease agreement.
Custom Lease You pay some amount up front and a monthly amount for the life of the lease agreement. Paying something upfront will often improve the economic return for you.
Prepaid Lease You pay the entire amount of the lease up front.
Power Purchase Agreement (PPA) A third party owns the system and you pay monthly or upfront for the energy it produces. PPA availability varies by State.
$0 Down PPA You pay nothing up front and agree to pay a monthly amount for the energy produced for the life of the agreement.
Custom PPA You pay some amount up front and then pay a monthly amount for the energy produced for the life of the agreement. Paying something upfront will often improve the economic return for you.
Prepaid PPA You buy all of the energy produced for the life of the agreement up front.

Compare Plans Page

Average Monthly Electricity Bill How much you pay for electricity on average over a 12 month period.
Energy Value The value of the energy your solar system will produce in its lifetime at the cost you would have paid for it from the utility company.
System Size The raw capacity of your system to generate energy. For residential solar systems this is usually shown in kilowatts (kW).
Electricity Usage Offset The percentage of your current electricity usage that will now come from clean, renewable solar power instead of the electricity grid.
CO2 Offset The amount of CO2 emissions that will be avoided if you go solar with this system. This estimate is based on your specific area. Utility companies in some parts of the country emit more CO2 per energy unit than others.
25 Year Total Cost Of Electricity The estimated amount you will pay for electricity over 25 years including increases in the cost of electricity over time.
Cost per kWh (avg) The estimated amount you will pay per kilowatt-hour of electricity you use averaged out over 25 years.
Annual Increase The estimated rate at which the cost of electricity will rise every year based on historical data for your area.
Monthly Electricity Payments The estimated amount you will pay for electricity from your utility per month averaged out over 25 years.
New Monthly Payment The estimated amount you will pay for electricity with solar and your utility, averaged out over 25 years.
Net System Cost The estimated amount you will pay once all the rebates and credits have been applied.
Down Payment The estimated amount you will pay upfront when you go solar.

Customize – Compare: 25 Year Costs & Savings (Common)

Average Price You pay the utility company for every unit of energy you use (kilowatt-hour or kWh). This average price is shown in cents per kilowatt hour. Using Average Price allows you to compare different solar plans, and also to compare those plans with utility energy.
Monthly Payment (avg) The estimated amount you will pay per month averaged over 25 years for electricity from that source (utility or solar).
Annual Increase The estimated percentage by which your payment (for solar or the utility) will rise every year.
Total Electricity Cost The estimated total amount you will pay over 25 years for electricity.
Total Cost of Solar The estimated total amount you will pay over 25 years for solar.
Electricity Bill Offset by Solar The percentage of your current electricity usage that will now come from clean, renewable solar power instead of the electricity grid.
Total Monthly Payments (avg) The estimated average amount of money you will pay to your utility and for your solar power (combined) each month and averaged over 25 years.
Total Savings What we estimate you will save from going solar over 25 years. This includes payments you might receive (depending on your local incentives) for generating renewable energy plus the money you that you didn’t have to pay your utility company.

Customize – Solar Energy System (Common)

System Size The raw capacity of your system to generate energy. For residential solar systems this is usually shown in kilowatts (kW).
25 Year Energy Production How much energy we estimate your system will produce over 25 years.
Electricity Usage Offset by Solar The percentage of your current electricity usage that will now come from clean, renewable solar power instead of the electricity grid.

Customize – Payments & Incentives With This Solar Plan (Cash)

Installed Price How much the system costs to build and install. This is the turnkey cost that includes equipment, installation, paperwork, etc.
Rebates & Credits The estimated amount you will receive from incentives in the form of Federal Tax Credits, State Tax Credits, State Rebates, local rebates, or utility rebates.
Net System Cost The estimated amount you will pay once all the rebates and credits have been applied.
Federal Tax Credit You can claim 30% of the system cost on your taxes as a credit on your Federal Tax Return. NOTE: For Lease and PPA systems, this incentive goes to the system owner, which in this case is the solar company
State Rebates & Credits The estimated amount of State rebate money and tax credits applicable to you.
Local Rebates & Credits The estimated amount of local and utility rebate money applicable to you.
Anticipated Lifetime PBI Some incentives are paid to you based on the actual or estimated energy your solar system will produce. This is what we estimate those incentives will be worth over the life of your system.
Performance Based Incentives (PBI) Some incentives are paid to you based on the actual or estimated energy your solar system will produce. This is what we estimate those incentives will be worth over the life of your system.
Total Cost The amount we estimate you will pay after all tax credits, rebates, and performance based incentives are accounted for over the life of the system.
Installed Cost per Watt This amount along with the system size determines the installed price.
Current Monthly Utility Bill (avg) The default estimated amount or the one you adjusted for the current cost of your electricity. See “Average Monthly Electricity Bill” above.

Customize – Payments & Incentives With This Solar Plan (Loan)

Down Payment The estimated amount you will pay upfront when taking out your loan.
Monthly Payment The estimated amount you will on your loan each month. Depending on the type of loan this amount may change over time. For example, your loan payment may be slightly higher before you receive your Federal Tax Credit back. You would then use the tax credit to pay off a portion of the loan and reduce your monthly payment.
Term The length of the loan.
APR The estimated Annual Percentage Rate of the loan. The final rate is dependent on your personal income situation and credit score(s).
Federal Tax Credit You can claim 30% of the system cost on your taxes as a credit on your Federal Tax Return. NOTE: For Lease and PPA systems, this incentive goes to the system owner, which in this case is the solar company
State Rebates & Credits The estimated amount of State rebate money and tax credits applicable to you.
Local Rebates & Credits The estimated amount of local and utility rebate money applicable to you.
Anticipated Lifetime PBI Some incentives are paid to you based on the actual or estimated energy your solar system will produce. This is what we estimate those incentives will be worth over the life of your system.
Installed Cost per Watt This amount along with the system size determines the installed price.
Current Monthly Utility Bill (avg) The default estimated amount or the one you adjusted for the current cost of your electricity. See “Average Monthly Electricity Bill” above.