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Solar thermal (ST) installations - also known as solar hot water (SHW) or solar water heating (SWH) - are not as common in upstate New York as solar electric or wind energy systems. They are, however, the most efficient and time tested of renewable energy systems. Solar thermal systems use sunlight to heat water then use that water to provide heat for domestic hot water and/or space heating needs. Yes, even in the cloudy and cold weather of upstate New York, these systems work.

If you are interested in learning more, read this page, check out pictures of our installations , then send us a secure Client Information Form for solar thermal systems. The online form gives us some basic information to begin to address your situation. Of course, you can simply give us a call or send e-mail with questions.

Please note: We frequently install ultra-efficient Navien tankless water heaters as an energy-saving complement to our solar thermal systems. The cost of this simple upgrade is often less than $2000 and the 30% Federal income tax credit applies to this as well as the solar thermal system. Give us a call for more information.

Solar Thermal (ST) Technology      (back to top)

The concept of solar thermal is simple. Water left in direct sunlight gets hot... think of a garden hose! Solar thermal systems can heat water to 180°F or even higher.

There are two types of solar thermal systems. The simplest and least costly is referred to as a domestic hot water (DHW) system which provides hot water for uses such as bathing and washing dishes. The second type, a solar space heating system, can offset a significant fraction of the heating requirements of a building in addition to providing DHW and are best matched with hydronic heating systems such as baseboard or radiant floor.

When sunlight strikes solar thermal collectors, the absorber plates in the collectors transfer solar heat energy to a non-toxic propylene glycol (PG)/water mixture - the heat transfer fluid (HTF). PG is a food-grade substance which acts as antifreeze for systems installed in freezing climates. The HTF is moved by a pump through a pressurized, closed loop of copper pipe running into a building where it heats water in a storage tank via a heat exchanger. The HTF then returns to the collectors to be reheated. The solar preheated water becomes the "cold" input to a conventional water heater. Because water entering the water heater has been preheated by solar, little (or no) energy is required of the conventional water heater to heat up the incoming hot water to useful temperatures. As such, a solar thermal system turns your existing water heater into a backup device for mid-winter and the occasional string of gloomy days.

Because solar preheated water can exceed the temperature needed by a boiler or backup water heater (especially in the summer months), mixing valves, pressure-temperature relief valves, and heat dissipation devices are typically used solar hot water systems. These safety devices ensure the longevity and efficiency of the system.

Collectors come in two types, flat plates and evacuated tubes. There are advantages and drawbacks to both types of collectors. The appropriate choice will depend on the intended uses for the system (DHW and/or space heating), the installation site, and aesthetics. Both types of collectors are mounted in such a way that they absorb as much sunlight as possible. The collectors can be mounted either on the roof (usually south-facing, but sometimes east-west) or on the ground, depending on accessibility and preference.

Ground-mounted ST systems are slightly more expensive to install because of the foundation work required to mount them securely and trenching for the buried HTF pipes. Ground-mounted systems can be oriented to be as efficient as possible, are not limited in size by the available roof space, and are much easier to keep free of debris and snow as compared to roof-mounted systems.

Roof-mounted ST systems are slightly cheaper to install and do not require trenching to route the solar loop back from the array. However, they are limited by the space available on the roof and also may not be able to be optimally oriented. Our system designers can help you make decisions to ensure that the system design is a good match for your situation. One size does not fit all.

Site Evaluations      (back to top)

In order to design a residential or commercial ST system, our system designers will come to your site to evaluate its solar potential. The fee for a residential site visit is $250 plus $1 per mile one-way travel beyond a 30-mile radius from Ithaca. The fee for a commercial site visit is $500 + travel for a single building/site and may increase with the number of buildings and sites involved. Please note that our Site Evaluation fee will be refunded in its entirety if you have us design and install a system for you.

For Residential clients, our Site Evaluation will result in the following deliverables:

1. Shading report - a highly detailed analysis with annotated images and dimensions of every roof surface clearly showing those roof areas which are useful for deployment of solar - as well as those which are not. If no roof surfaces are appropriate or desired, then sites on the property suitable for ground-mounted solar are analyzed for shading.
2. Energy usage report - an analysis based on Customer-supplied bills or on a Utility-supplied usage summary showing what fraction of present or historical energy usage can be offset by solar thermal.
3. Customer Purchase Agreement (CPA) - consisting of a detailed Project Description, datasheets for major system components, itemized materials and labor costs, anticipated incentive payments (if any), and estimated tax credits.

For Commercial clients:

1. Shading reports - highly detailed analyses with annotated images and dimensions of every roof surface clearly showing those roof areas which are useful for deployment of solar thermal on one or more buildings that are identified by us as having useful solar generation potential.
2. Energy usage reports - analyses based on Customer-supplied bills or on a Utility-supplied usage summary for one or more meters at the buildings/sites visited.
3. Solar Thermal feasibility report - giving specific suggestions and estimated costs for the design, installation and commissioning of one or more ST projects at the buildings/sites visited. Next steps in the process are clearly articulated here.
4. Economic analyses - for all projects described in the Solar Thermal feasibility report.

Home Energy Use      (back to top)

Everyone knows that heating a building is expensive, but too often we pay the bills and forget that we should have control over energy use. Space heating uses over half of all the energy used in a home. When the energy used for space heating and DHW is combined, they comprise over 3/4 of a home's total energy demand. Installing a solar thermal system can radically reduce the amount of conventional fossil-fuel energy that you must pay for.

The information in the graph above is from a 2005 Energy Information Administration report and should be a powerful argument to reconsider the way we use energy in our homes. Making sure our electricity is generated sustainably is an important step in the right direction, but efforts to promote sustainability cannot stop there. Finding ways to heat our homes and businesses sustainably is clearly of vital importance. Solar thermal systems are a valuable tool in decreasing the amount of non-sustainable fossil fuel energy required to heat a home.

Cost Estimates      (back to top)

System Size (collectors)	Storage Tank Size (gallons)	Mount Style	Total Cost	NYS Income Tax Credit	Fed Income Tax Credit	Total Tax Credit	Final Cost
Domestic Hot Water Systems
2	60 - 80	Roof	$15,000	-$3,750	-$4,500	-$8,250	$6,750
		Ground	$18,000	-$4,500	-$5,400	-$9,900	$8,100
3	100 - 120	Roof	$17,000	-$4,250	-$5,100	-$9,350	$7,650
		Ground	$20,000	-$5,000	-$6,000	-$11,000	$9,000
Space Heating Systems
4	200	Roof	$22,000	-$5,000	-$6,600	-$11,600	$10,400
		Ground	$26,000	-$5,000	-$7,800	-$12,800	$13,200
6	400	Roof	$25,000	-$5,000	-$7,500	-$12,500	$12,500
		Ground	$30,000	-$5,000	-$9,000	-$14,000	$16,000
8	500	Roof	$30,000	-$5,000	-$9,000	-$14,000	$16,000
		Ground	$36,000	-$5,000	-$10,800	-$15,800	$20,200

Notes:

• Roughly speaking, one collector produces enough hot water to meet the DHW needs of an average adult.
• The output of 16 evacuated tubes is approximately equal to 1.5 to 2 flat plate collectors.
• Price estimates are for the complete system. This includes labor costs, installation, materials, and design.
• These prices are rough estimates and do not take into account considerable variation in the plumbing labor involved. For more detailed price information, please contact us.

Simple payback times realized by energy savings are estimated at around 8 to 12 years depending on the inflation rate of the displaced conventional energy source (electric, gas, oil) during this period. However, a simple payback analysis does not take into consideration intangibles such as greatly reduced carbon dioxide emissions over a system's 20 to 30 year lifespan. The return on investment (ROI) over a system's service life is a far better measure of value. Please contact us for a detailed economic analysis.

Incentives and Tax Credits      (back to top)

There are state and federal income tax credits available for the installation of solar thermal systems. The New York state income tax credit is 25% of the total expenditures for the system, but is capped at $5,000. The Federal income tax credit is equal to 30% of total system cost with no cap. As such, this credit can offset a significant amount of the "total" or "basis" project cost (a term which the Solar Energy Industry Assocation (SEIA) interprets in their Federal Solar Energy Incentives FAQ to mean before any incentives have been applied). To claim the credit or for more detailed information, refer to Federal tax form 5695. The 2009 form states If you cannot use all of the credit because of the tax liability limit..., you can carry the unused portion of the credit to 2010. It seems reasonable to assume, by implication, that the carryforward can continue for as many years as required to claim the entire amount of the credit.

More information on current legislation is available at the Database of State Incentives for Renewables and Efficiency.

Heating a Pool      (back to top)

One very popular use for solar thermal is to heat a swimming pool. In general, systems designed exclusively for pool heating are usually not designed to operate year round. As such, these systems tend to be far less costly, low-tech designs that work well to heat a pool, but are unsuitable for other heating applications. That said, the design of DHW and supplemental space heating systems described above can also be easily extended to heat a pool.

Also, please note that systems designed exclusively to heat a pool are typically not eligible for state and Federal income tax credits. However, systems that also provide DHW and/or supplemental space heating in addition to pool heating may be eligible for these credits. Please contact us for more information about this.