Solar Heating
We feel we have the best solar heating option available in Michigan today. While it is not necessarily the lowest cost system we feel it is the option that makes the most sense. Also, we should say right up front that while Michigan has a good overall solar resource it is not as good in the dead of winter as it is in some other northern states. We tend to market heating systems as a spring and fall product. This fact has greatly effected our choice in which products to carry. Also, make sure the house is well insulated and weatherized, which is beyond the scope of this website.
Learn about different types of Solar Heating Systems |
Back to top |
Passive Solar
If you are building, remodeling, or replacing windows, passive solar heating is an excellent thing to do. It is simpler than the active solar options and, if done right, can readily collect up to 40% of your heating needs from the sun. We say readily and 40% because when you start trying to get more the returns diminish a bit. We dont want to discourage people that want to try for more. That is one kind of excess we are in favor of. Just make sure your approach it realistic. Good passive design will have fewer windows that dont let much heat in on the east and west facing walls, and windows that let the suns heat in on the south side of the structure. You can also use mass to store the heat. One limitation of passive design is that the south side tends to be warmer than the rest of the house. We dont actually deal in windows and building at this point, so our recommendation is to hire an architect and builder that have a track record with good passive design. There is much more to learn about passive solar, but it is beyond the scope of this website as it is not our core competency. We believe its a good way for clients to spend money even if it is not one of our revenue streams.Solar Hot Air
Another type of solar heating SUR has installed but does not carry uses an active, engineered solar collector to heat air. It then may use fans, thermosyphoning, ducts or no ducts to get the heat from a south wall or rooftop collector into the living space. Often this is controlled with a separate thermostat.If a system is installed just to do heating in Michigan it suffers from one problem: winter solar resource. If you pay the same for a system to heat the home as you would to heat water you have thrown money at a product that will lie dormant in the season with the best resource- the summer. It will add value in spring and fall, and any winter day that is sunny. Many people that have these systems LOVE them, and swear by them because they know on a sunny day in the heating season the furnace runs less. But in most circumstances we feel there will be a better return on summer heat loads that would otherwise use fossil fuels.
To make better use of the capacity that is installed some solar-hot-air dealers will do a dual mode air system. These systems heat the air and use an air to liquid heat exchange coil to get solar hot water from the hot air mix. This improves the usage of the system but we have decided not to sell these systems in favor of our solar hot-water-with-heat system described below.
Solar Hot-Water-With-Heat
Our solar hot-water-with-heat system uses an oversized drainback system that has the collectors at a steeper winter angle. The solar hot water can be used for domestic hot water needs or go through a heat exchange coil in the furnace to blow solar heat throughout the house. The systems will work even better with radiant floor heat. If you have radiators on the wall, the temperature needed will be too high for solar hot water to be effective with flat plate collectors.The real advantages of solar-hot-water-with-heat over other heating systems are capacity and storage. For anyone using much hot water in the summer solar hot water is the low hanging fruit in the renewable energy mix. Our over-sized hot water with heating systems will get a higher percentage of your hot water from the solar system. This is done more efficiently than using the air to liquid heat exchange coil mentioned above in the solar-hot- air section.
Having a little extra storage in the form of hot spring and fall water also lends the following advantage. Solar-hot-air system owners that want to get the most out of hot air systems will heat the house up to the highest temperatures they can stand in order to store the heat in the building. This increases utilization and keeps the collectors working efficiently. With our system, there is less need to heat the house up because the heat can be stored in the water tank to be used as needed. Not using the heat right away will get you a little less heat for the same reason it would with a hot air system, but on a nice spring day wed rather open the windows and enjoy the new weather than keep them closed in order to store heat for night-time use.
An important concept that is a bit counter-intuitive is the idea that using up solar heat as soon as it is collected actually increases the amount of heat collected. Thats right, if you can use up the heat and draw the temperature down in the tank the solar panels/collectors will bring in more heat than if you hadn't. They have an efficiency curve, and they operate more efficiently at lower temperatures because they will spill less heat to the atmosphere if the fluid is cooler. For this reason using the solar heat and hot water usage increase the efficiency. In spite of this fact, in terms of overall consumption we don't encourage people to WASTE the heat that has been collected, it just means by using the energy as planned you will be getting more energy out of the large collector area.
How much energy will the solar heating panels collect? |
Back to top |
How much do solar heating systems cost? |
Back to top |
