Solar Hot Water

Solar hot water systems use the energy of the sun to heat your home’s water supply. This technology is entirely renewable, and installing it can benefit both the environment and your wallet!

How Solar Hot Water Works

Generates warm water for your home using the sun’s thermal energy

Can supplement your regular water heater

Has the potential to eliminate your entire water heating bill

Works well in cold climates

Interested in exploring solar thermal solutions for your home?​

Connect with local, vetted contractors to understand your options.

Incentives for Solar Hot Water

Mass Save HEAT Loan

If you’re installing solar hot water, you may be eligible for a 0% interest HEAT Loan from Mass Save to finance the project. You can borrow up to $25,000 for home energy efficiency upgrades. Find out more about Mass Save’s HEAT Loan program. 


Cambridge residents installing a solar hot water system qualify for the Alternative Energy Certificate (AEC) program. With this program, you can receive certificates based on the energy production of your solar hot water system. You can sell these certificates to utilities for extra cash. The revenue earned from these certificates will help you to further decrease your overall investment for solar hot water. Learn more about AECs.


The State of Massachusetts provides a state tax credit of up to $1,000 for solar hot water installations. In addition, the Massachusetts Clean Energy Center (Mass CEC) provides rebates of up to $4,500 to help lower your upfront cost of installing a solar hot water system. Learn more about this state tax credit, or read about the Mass CEC’s solar hot water rebate program.

Do You Live in a Multi-Family Building?


Many Cantabrigians live in shared buildings. If you live in a multifamily air source, solar hot water systems are a good solution to heat your water supply. That said, there are extra considerations to take when installing this technology on a shared property. Our no-cost Retrofit Advisor can help your apartment or condo building learn more about suitable clean heating and cooling options and help you find ways to finance your project.

or call 617-301-6207 to get started.

Does Solar Thermal Work in the Winter?

Just like solar electric panels, your solar thermal panels will work during the wintertime. They will generate less hot water than in sunnier months, so you may have to use your backup water heater more often during cold weather. Any snow that is accumulated on the panels will typically slide off on its own when the sun comes back out. Solar thermal systems installed in Cambridge will also have freeze protection.

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Solar Hot Water in Action

These condo owners worked with their neighbors to avoid conflict when installing their solar hot water system

A solar thermal system lowered costs for a water-intensive home-based business

Inspired by her brother’s solar panels in California, this condo owner installed a small solar system on her historic building

This architect found the safest and best route to installing a solar hot water system in his home

Using state and local incentives, this family saved approximately $9,000 on their solar hot water system

Though he saved a bundle, this homeowner ran into a few headaches during the installation process

The new solar hot water system has garnered as much interest from neighbors as the Big Boy in the yard!

Download all these solar hot water case studies together in a single document

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