Energy efficiency starts with good design. Of course the efficiency of nearly any home can be improved, but designing for energy efficiency is always going to yield the best results.
Depending on the status of your project, there are priorities to consider that will have an impact on the energy performance of the structure.
1. Property Selection - View lots are the most common to create challenges with home energy use. Ideally southern views are going to be beneficial and western views the most detrimental. Additionally the shape of the lot can affect the length axis of the home with positive or negative effects on energy use.
2. Solar Orientation - Once property has been selected, the structure should be oriented to capitalize on the seasonal arc of the sun. In the northern hemisphere it's preferred to orient windows to the southern exposure and prevent heat gain on the east and west elevations.
3. Passive Solar Design - The sun can heat our homes in the winter and even help keep us cool in the summer - for free, when passive solar design techniques are used. In this approach, the building itself or some element of it takes advantage of natural energy characteristics in materials and air created by exposure to the sun. Passive systems are simple, have few moving parts, and require minimal maintenance and no mechanical systems.
4. Reduce Energy Demand - Some of the most effective methods to reduce energy use include: increased insulation values and weathertightness; HVAC zoning and programmable thermostats; CFL and LED lighting; and behavior modification.
5. Increase Efficiency - Increased energy efficiency is available for a number of building systems. This is where cost-benefit analysis becomes important. Depending on the success of the previous strategies, there may be a point of diminishing returns from the investment in higher performance products. Windows and HVAC systems are the main items to fall into this category.
6. Solar Thermal Heating (and Cooling) - Solar hot water heating is a type of thermal heating strategy but did you know that thermal solar collectors can also be used to heat the inside of the house? This is called hydronic heating and is actually quite comfortable and can be affordable. Additionally, in the right application solar thermal panels can actually be used to cool your home in the summer time.
7. Alternate or Renewal Energy - The final upgrade to consider is the addition of an alternate energy source like photo-voltaic panels or a renewable source like a micro-hydro generator. Recent industry articles indicate the cost of PV (photo-voltaic) over their lifetime, is getting close to power purchased from utility companies. Additionally, if PV panels are amortized over a 15-year mortgage period, the cost saving and interest tax deduction may exceed the cost of purchased power. Let us help you make the calculations.
CFLs (Compact Fluorescent Lighting) are available in a variety of styles or shapes. Some have two, four, or six tubes. Older models, and specialty models, have separate tubes and ballasts. Some CFLs have the tubes and ballast permanently connected. This allows you to change the tubes without changing the ballast. Others have circular or spiral-shaped tubes. In general, the size or total surface area of the tube determines how much light the bulb produces.
Benefits:
- Efficient: CFLs are four times more efficient and last up to 10 times longer than incandescents. A 22 watt CFL has about the same light output as a 100 watt incandescent. CFLs use 50 - 80% less energy than incandescents.
- Less Expensive: Although initially more expensive, you save money in the long run because CFLs use 1/3 the electricity and last up to 10 times as long as incandescents. A single 18 watt CFL used in place of a 75 watt incandescent will save about 570 kWh over its lifetime. At 8 cents per kWh, that equates to a $45 savings.
- Reduces Air and Water Pollution: Replacing a single incandescent bulb with a CFL will keep a half-ton of CO2 out of the atmosphere over the life of the bulb. If everyone in the U.S. used energy-efficient lighting, we could retire 90 average size power plants. Saving electricity reduces CO2 emissions, sulfur oxide and high-level nuclear waste.
- High-Quality Light: Newer CFLs give a warm, inviting light instead of the "cool white" light of older fluorescents. They use rare earth phosphors for excellent color and warmth. New electronically ballasted CFLs don't flicker or hum.
- Versatile: CFLs can be applied nearly anywhere that incandescent lights are used. Energy-efficient CFLs can be used in recessed fixtures, table lamps, track lighting, ceiling fixtures and porchlights. 3-way CFLs are also now available for lamps with 3-way settings. Dimmable CFLs are also available for lights using a dimmer switch.
LEDs (Light Emitting Diodes) are solid light bulbs which are extremely energy-efficient. When first developed, LEDs were limited to single-bulb use in applications such as instrument panels, electronics, pen lights and, more recently, strings of indoor and outdoor Christmas lights.
Manufacturers have expanded the application of LEDs by "clustering" the small bulbs. Today, LED bulbs are made using as many as 180 bulbs per cluster, and encased in diffuser lenses which spread the light in wider beams. Now available with standard bases which fit common household light fixtures, LEDs are the next generation in home lighting.
Benefits:
- Long-lasting - LED bulbs last up to 10 times as long as compact fluorescents, and far longer than typical incandescents.
- Durable - since LEDs do not have a filament, they are not damaged under circumstances when a regular incandescent bulb would be broken. Because they are solid, LED bulbs hold up well to jarring and bumping.
- Cool - these bulbs do not cause heat build-up; LEDs produce 3.4 btu's/hour, compared to 85 for incandescent bulbs. Common incandescent bulbs get hot and contribute to heat build-up in a room. LEDs prevent this heat build-up, thereby helping to reduce air conditioning costs in the home.
- Mercury-free - no mercury is used in the manufacturing of LEDs.
- More efficient - LED light bulbs use only 2-17 watts of electricity (1/3rd to 1/30th of Incandescent or CFL). LED bulbs used in fixtures inside the home save electricity, remain cool and save money on replacement costs since LED bulbs last so long. Small LED flashlight bulbs will extend battery life 10 to 15 times longer than with incandescent bulbs.
- Cost-effective - although LEDs are initially expensive, the cost is recouped over time and in battery savings. LED bulb use was first adopted commercially, where maintenance and replacement costs are expensive. But the cost of new LED bulbs has gone down considerably in the last few years. and are continuing to go down. Today, there are many new LED light bulbs for use in the home, and the cost is becoming less of an issue. To see a cost comparison between the different types of energy-saving light bulbs, see our Light Bulb Comparison Charts.
- Light for remote areas and portable generators - because of the low power requirement for LEDs, using solar panels becomes more practical and less expensive than running an electric line or using a generator for lighting in remote or off-grid areas. LED light bulbs are also ideal for use with small portable generators which homeowners use for backup power in emergencies.
Electric lighting burns up to 25% of the average home energy budget. The electricity used over the lifetime of a single incandescent bulb costs 5 to 10 times the original purchase price of the bulb itself.
Additionally, the heat created by incandescent lighting adds to the latent heat-load and requires the air-conditioning system to work harder to remove it. This is especially an issue in the southern home.
Compact Fluorescent Lights (CFL) and Light Emitting Diode (LED) bulbs have revolutionized energy-efficient lighting.
CFLs are simply miniature versions of full-sized fluorescent lights. They screw into standard lamp sockets, and give off light that looks similar to the common incandescent bulbs - not like the fluorescent lighting we associate with factories and schools.
LEDs are small, very efficient solid bulbs. New LED bulbs are grouped in clusters with diffuser lenses which have broadened the applications for LED use in the home. LED technology is advancing rapidly, with many new bulb styles available. Initially more expensive than CFLs, LEDs bring more value since they last longer. Also, the price of LED bulbs is going down each year as the manufacturing technology continues to improve.
As a new empty-nester couple, our power and water (and grocery) bills have dropped substantially now that our kids have moved out of the house. I learned conservation from my father, who wouldn’t turn on the AC until he saw beads of sweat running down your forehead. While I’m not quite that extreme, I do take a “military shower”, as Dad referred to it. I turn the shower on to get wet, then turn it off to lather up, and then turn it back on to rinse. My shower water usage doesn’t exceed a minute; a fraction of time compared to our now absentee family members.
Behavior and attitude may have the most impact on our energy and water use. While my habits help me save, there are some strategies to consider when building a new home that can help you conserve too.
- Solar orientation, natural lighting and shading, take advantage of the seasonal arch of the sun, to provide light and heat when it’s wanted, and prevent excess heat gain when it’s not.
- Zoning and programmable thermostats allow you to control the AC and heating in the areas of the house where you spend your time, effectively reducing the amount of living space that has to be conditioned.
- Stand-alone dehumidification increases comfort at a set temperature without running the AC. The saying, “It’s not the heat, it’s the humidity”, was probably coined here in central Florida.
- Lighting design and control can reduce the number and length of time electric lighting is needed, but still maintain security and convenience.
- Operable windows can be oriented to catch breezes and exhaust heat, while still providing security and allowing use during rainy weather.
- Native Florida landscaping that has adapted to the environment, requires less water and maintenance while adding to the beauty of the property.
- A convenient location to line-dry clean laundry saves energy used by the dryer and extends the life of clothing and linens, all while adding a crisp, clean feel.
These are a some of the ideas that can greatly reduce energy and water use, plus there are also many other ways to reduce demand and increase efficiency with the design and construction of a new home. Look for more posts on these subjects soon. Keith Groninger
Energy efficiency starts with good design. Of course the efficiency of nearly any home can be improved, but designing for energy efficiency is always going to yield the best results.
Depending on the status of your project, there are priorities to consider that will have an impact on the energy performance of the structure.
1. Property Selection - View lots are the most common to create challenges with home energy use. Ideally southern views are going to be beneficial and western views the most detrimental. Additionally the shape of the lot can affect the length axis of the home with positive or negative effects on energy use.
2. Solar Orientation - Once property has been selected, the structure should be oriented to capitalize on the seasonal arc of the sun. In the northern hemisphere it's preferred to orient windows to the southern exposure and prevent heat gain on the east and west elevations.
3. Passive Solar Design - The sun can heat our homes in the winter and even help keep us cool in the summer - for free, when passive solar design techniques are used. In this approach, the building itself or some element of it takes advantage of natural energy characteristics in materials and air created by exposure to the sun. Passive systems are simple, have few moving parts, and require minimal maintenance and no mechanical systems.
4. Reduce Energy Demand - Some of the most effective methods to reduce energy use include: increased insulation values and weathertightness; HVAC zoning and programmable thermostats; CFL and LED lighting; and behavior modification.
5. Increase Efficiency - Increased energy efficiency is available for a number of building systems. This is where cost-benefit analysis becomes important. Depending on the success of the previous strategies, there may be a point of diminishing returns from the investment in higher performance products. Windows and HVAC systems are the main items to fall into this category.
6. Solar Thermal Heating (and Cooling) - Solar hot water heating is a type of thermal heating strategy but did you know that thermal solar collectors can also be used to heat the inside of the house? This is called hydronic heating and is actually quite comfortable and can be affordable. Additionally, in the right application solar thermal panels can actually be used to cool your home in the summer time.
7. Alternate or Renewal Energy - The final upgrade to consider is the addition of an alternate energy source like photo-voltaic panels or a renewable source like a micro-hydro generator. Recent industry articles indicate the cost of PV (photo-voltaic) over their lifetime, is getting close to power purchased from utility companies. Additionally, if PV panels are amortized over a 15-year mortgage period, the cost saving and interest tax deduction may exceed the cost of purchased power. Let us help you make the calculations.
