Tip: Clean and Efficient Heating

September's Sustainable Living Tip

Take advantage of state and federal incentives to improve your home's heating efficiency, then start  switching away from fossil fuel to heat your home. Solar supplemented by electricity is the most sustainable heating system, and it's easy to get started.

 

Facts about Clean and Efficient Heating

1. Conventional houses waste 90% or more of the energy they use for space heating, compared to houses built to the Passive House standard.
2. The Passive House standard is the industry leader in energy efficiency, having been successfully pioneered in Europe and now reaching Maine.
3. Federal and state incentives are available to improve the energy efficiency of existing homes, including up to $4,500 through Efficiency Maine's Home Energy Savings Program.
4. The key to achieving the dramatic improvements in home heating efficiency necessary to reach the Passive House standard is to air seal the building envelope and provide fresh air ventilation using a heat recovery ventilator.
5. Another important aspect of Passive House design is to use passive solar gain, which can be achieved through windows and solar air space heaters that ensure solar energy can enter the home during the day, but prevent heat from leaking back out at night.
   
6. Houses built to the Passive House standard in Maine will maintain a temperature of at least 10 degrees C (50 degrees Fahrenheit) throughout winter when their ventilation and heating systems are turned off. You can leave these houses unheated in the winter without risk of freezing. Passive House heating systems are needed only for comfort.
   
7. While it is challenging to retrofit many existing homes to Passive House standards, the principle of controlling air flow can be applied to every home to improve its heating performance.
8. A professional energy audit is the first step to qualify for state funding under the Home Energy Savings Program.
9. A good energy audit will help you understand how your home uses energy, so you can prioritize your energy upgrades.
10. A blower door test, which uses a big fan to suck air out of your house, is one of the best ways to identify air leaks and to check that home energy work has been done properly.
11. An infrared scan, using a camera that measures surface temperatures, is another important diagnostic tool that allows you and your contractors to see where energy leaves your house.
12. In most existing homes, it is not cost effective to control all air leaks; enough air will flow uncontrolled in and out of the structure to maintain healthy indoor air quality.
13. But if you are able to control air leaks to the point where a blower door test shows fewer than 0.3 air changes per hour during the heating season, then you should install a heat recovery or energy recovery ventilator.
14. Heat recovery ventilators exhaust stale outdoor air and bring in fresh outdoor air in a way that transfers heat from the outgoing air to the incoming air. This helps maintain a higher indoor air temperature, but can lower indoor relative humidity because outdoor air is usually dryer than indoor air.
15. Energy recovery ventilators perform the same function as heat recovery ventilators, but also help transfer humidity to maintain not only a higher indoor air temperature but also a higher indoor air relative humidity.
    
16. If a ventilator fails, windows can be opened to provide fresh air.
17. As homes are "tightened up" by sealing places where cold air enters and warm air leaves, it becomes more important to consider ways to maintain indoor air quality.
18. It is a good idea to choose paints, finishes, and cleaning products that do not emit noxious fumes. A surprising number of household products contain petroleum-based fragrances that irritate human respiratory systems.
19. As you improve your home's energy performance, you increase the affordable options for heating your home.
    
20. A conventional 2,500 square foot home in Maine that is not well insulated would require a heating system rated between 30,000 and 40,000 watts. This is equivalent to about 24 electric space heaters.
21. Doubling the efficiency of this home would allow it to be heated with 12 space heaters; raising it to Passive House standards would allow the entire house to be heated with just three electric space heaters which would typically be integrated with the ventilation system.
22. Solar space heaters are a way to turn conventional homes into passive solar homes. These units can be installed on a southern wall or roof. Without the need for electricity or plumbing, they circulate air from inside your home, through a heat collector, and back into your home, effectively harnessing the free energy that is delivered to your home every sunny winter day.
    
23. In the long term, our society must make the transition away from burning all types of fossil fuel, including propane and natural gas.
    
24. Although a fraction of our electricity here in Maine is generated by burning fossil fuel, much of it is already sourced from clean renewable sources.
25. In the future, we can generate all of our electricity from clean and renewable sources here in Maine.
26. If you want to help jump start the conversion of our economy to a sustainable clean energy future, you can install a grid-tied renewable energy system. The most reliable systems use solar photovoltaic panels. The electricity you generate will flow into the grid, displacing the need to generate electricity from non-renewable resources.
    
27. With current technology, it is much easier to stop burning fossil fuel for home heating than to stop burning fossil fuel for transportation, so it makes sense to start our society's transition to clean energy by changing the way we heat our buildings.
28. One of the advantages to using electricity for home heating, from the perspective of the overall sustainability of our society, is that the delivery system for electricity is largely in place. Since most homes already use electricity for lighting and appliances, we are committed to maintaining this infrastructure.
29. Building a new distribution system for natural gas throughout Maine is an unsustainable and unnecessary expense. Private and public funds will be tied up in this venture that could be better put to use increasing the heating performance of our housing stock and improving the reliability of our electric grid.
30. Delivering cord wood or pellets throughout Maine places a huge burden on our roads.
    
31. Although work is being done to develop renewable sources of solid and liquid fuels, these energy strategies do not lend themselves as easily to distributed production as electricity generation.
32. Most homes and businesses in Maine with a sunny roof can be used to generate electricity; few residential and commercial properties are suitable for fuel production.
33. The heating systems of the past were based on wood; the systems of the present require fossil fuel; those of the future will likely be solar electric.
34. If you are building a new house, you can be part of the solution for a clean energy future by choosing to build to the Passive House standard.
    
35. If you plan to live in an existing house, you can still help bring about a clean energy future by improving your home's heating performance, installing a solar space heater, and switching your home to electric heat room by room.