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Solar Thermal Frequently Asked Questions

What is solar thermal?
Solar thermal is a technology that utilizes the sun’s rays to generate heat, which is then used to heat (or cool) water or other fluids for a variety of applications.

What is the difference between solar thermal and photovoltaic (PV) solar technology?
Solar thermal systems generate heat whereas photovoltaic (PV) solar systems generate electricity.

How does a solar thermal system work?

Collectors (panels) mounted on a roof or on a ground-mounted structure absorb solar energy. Solar-heated fluids moving through the collector transfer their thermal energy to water stored in solar storage tanks, which feed the primary water-heating system. When fed with solar-heated water, the fossil fuel-powered water-heating system is either not activated, or activated for less time.

How can solar thermal benefit a business?
The two main benefits of solar thermal for commercial clients are reduced energy bills and reduced carbon footprint. A solar thermal system provides long-term financial benefits by reducing monthly utility bills while also helping you go green.

What type of businesses can benefit from solar thermal?
Solar thermal can benefit any business or facility that relies on large quantities of hot water or other heated fluids. Organizations facing sustainability mandates from shareholders or the government can also benefit from solar thermal.

How much money will a solar thermal system save me?
Savings vary widely depending on system size, application and how energy is being used in the building. A site analysis is the first step toward reaching an accurate, project-specific figure on system savings.

How much does a solar thermal system cost?
As with any business investment, there is an upfront cost to installing a solar thermal system. Power Purchase Agreements, and various rebates and tax credits, can remove or substantially reduce the upfront cost. Over time, the money that the system saves you adds up to several times the system cost. A site analysis is the first step toward reaching an accurate, project-specific figure on system cost.

How much of my yearly hot water load will a solar thermal system offset?
Appropriately sized systems can offset 60-80% of the annual hot water load.

Will my building still have hot water on cloudy days, or if the system breaks down?
Yes. Because solar thermal systems supplement the building’s existing water-heating equipment (i.e, a boiler) the building will always have hot water.

Can a solar thermal system work with an on-demand water heater?
Yes. This is a good solution for projects with space limitations.

If I install a solar thermal system, can I still keep my regular water heater?
Typically, yes. There are also one-tank systems available that are a combination of a solar hot water tank and a natural gas-powered water heater.

Can’t I just use solar electric (PV) to offset my hot water load?
For a very high cost. You would pay over five times more to heat your water with a solar electric (PV) system and use over six times the roof space. A better solution is a solar water heater with an electric back-up that can be offset by a PV system.

Do I need to acquire a building permit before having a solar thermal system installed?
SunWater Solar will acquire the permit for you. The permit fee is factored into the price of the installation.

Do the solar thermal collectors (panels) need to face due south?
No. Though due south is ideal, the collectors can be installed up to 90 degrees off of due south with minimal impact on energy production.

What is Concentrated Solar Power (CSP)?
CSP solar thermal systems are utility-scale installations that use lenses or mirrors to focus solar rays onto a reservoir of fluid. The fluid boils, creating steam that powers a turbine, which produces electricity.


Making hot water from the sun...

SunWater Solar is a design/build company based in the San Francisco Bay Area, specializing in solar water heating systems. The company provides these systems for many types of commercial projects. More»

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