Want To Save Energy - Learn To Control The Heat.
Saving energy is mostly about heat management
Saving energy is mostly about heat management. Energy is heat. We're going to cover 10 basic actions designed reduce energy usage in your home. You can apply these principles to both new construction and existing homes.
First, let's cover some basic physics:
A. Heat energy flows from hot to cold. Its speed of flow increases as the difference between temperatures increases
B. Heat flow can be reduced by insulation.
C. Heat can be made to go from cold to hot. To do this, it requires a heat pump. Air conditioners are heat pumps. A quantity of heat can be pumped much cheaper than it can be created - about a third the cost.
D. Any heat that enters your home during the summer must be removed by your air conditioner.
E. Glass can act as a one-way check valve for the sun's energy. It will pass that energy into the house but will not pass it back out due to certain physical laws. This is called the "greenhouse" effect.
F. Anything that acts by its own nature and does not require input of additional energy is considered a passive operation.
Okay - so based upon these simple rules, here are 10 basic actions that will improve a home's energy efficiency which will save you money. I'll mention the rule and then what you can do:
1. Rule B - Insulate your home to the max. Few actions will give you a better cost to benefit ratio. This is also passive (rule F).
2. Rules D and E - Large overhangs - this reduces sunlight into the home which would have to be removed. This is passive (rule F).
3. Rules D and E - Reduce or block windows on the western side. If you are designing a new home this can be easy. This is passive (rule F)
4. Rule E - Use reflective glass. Shades and curtains will not work. They will heat up yet not pass the heat back out the window. Your air conditioner will have to remove that heat. You must stop the heat before it goes through the glass. This is a passive method and will save you lots of energy and money in the summer time.
5. Rule A - Placing foil under the plywood roof sheathing of your home is a very effective way to keep your attic cooler. This is easiest to do while building a new home. If your home exists, then consider a radiation barrier in the attic. This will keep the attic cooler. This is also passive (rule F)
6. Rule A - Attic ventilation, either passive or active, can be important to reduce the attic temperature. This will reduce the rate of heat flow from the attic to the cool house. Power ventilation is not passive but is considered by many to be most effective. It is activated by a thermostat which operates during the hot times of the day. A plus point of this is that it does not operate in the winter when you actually want heat to enter the home. In warmer states, such as Florida, a passive system of ridge vents or turbines will work well. These operate passively as the air moves by them. Remember that you will always need vents for both air into the attic and air that leaves the attic. Eave ventilation is important.
7. Rules A and B - Your air conditioning ductwork is exposed to attic heat which flows into the cool air that flows through them. Placing these ducts inside the air conditioned space of the home will significantly reduce heat flowing into the ducts. Another way is to place good insulation over top of the ducts to help isolate them from the attic heat. This is also passive (rule F).
8. Rule D - Water heaters should be outside of any air conditioned space. They leak heat. If they leak heat into the home then the air conditioner has to remove it. This action is passive.
9. Rule D - Dryers, even when vented properly, still produce heat which must be removed by the air conditioner during the summer. These should, like the water heaters, be placed outside of conditioned space. This action is passive (rule F)
10. Rule C - Water heaters heat their water with heating coils. This is the creation of heat and is relatively expensive. Alternatively one can take advantage of the savings of pumping heat by installing a system which takes the waste heat that is being pumped to the outside by the air conditioner and routing it into the water. This allows for the heat to be pumped into the water (which is cheaper) though, actually, during operation, it is totally free since the AC is pumping heat to the outdoors anyway. This is an excellent way to save energy and money.
Considering the basic rules you can think of your own ideas of ways to save energy and money.
by: Ken Risley