September 2008 Archives
LCD flat screen TVs can save 40% vs. plasma screen TVs. Wow! The savings can be more significant than an energy efficient refrigerator! That says something about how much TV we watch. You might also consider turning the TV off more often and getting together with friends or nature to enjoy real pleasures!
But back to energy and appliances :-) ...
TIVO and DVRs also use a lot of energy!
Design controllable circuitry to allow turning off all modules of a home entertainment center other than your DVR.
Provide similar circuits to your home office to allow grouping all your computers and peripherals except your CPU and wireless router.
And in the kitchen -- consider using induction cooking if you use electric; and add a real outdoor venting system that will improve your indoor air quality at the same time it takes unnecessary heat out of your conditioned spaces.
But back to energy and appliances :-) ...
TIVO and DVRs also use a lot of energy!
Design controllable circuitry to allow turning off all modules of a home entertainment center other than your DVR.
Provide similar circuits to your home office to allow grouping all your computers and peripherals except your CPU and wireless router.
And in the kitchen -- consider using induction cooking if you use electric; and add a real outdoor venting system that will improve your indoor air quality at the same time it takes unnecessary heat out of your conditioned spaces.
You've probably noticed the side-loading clothes washers and wondered if they really save energy and water!
Yes, and YES!
Horizontal axis clothes washers cut power by 30% or washing and reduces water use by requiring less in the tub for each load.
You can also reduce dryer energy by 10 to 20% by using the new appliances designed for energy efficiency. Look for the ENERGY STAR label to ensure that you're getting models with the best energy efficiency.
If you have Solar PV cells or a Solar Thermal system...run your wash in the afternoons with solar hot water and solar power!
You can also save energy by hanging your clothes to dry. Indoors. Outdoors....take your choice...they are both zero energy options!
Energy Star Dishwashers
If you're the kind of cook who absolutely refuses to wash your dishes in the sink -- which is far more energy and water efficient than an appliance -- be sure to select the highest efficiency model using Energy Star rating. Look for the Energy Guide label.
Where you place your dishwasher and clothes washer can also save you money. By keeping the (Insulated pipes, of course!) plumbing lines to the waer heater SHORT, you save temperature cooling. And consider designing your water heater close to both kitchen and bathrooms for greatest building and energy economy!
Designing your energy and water infrastructure for efficiency is step one in energy savings. Nothing can make up for large houses, long distance plumbing, or inefficient applieances. And you can end up paying many times the initial cost of the construction in your rising energy bills! Think ahead to save for years to come.
Yes, and YES!
Horizontal axis clothes washers cut power by 30% or washing and reduces water use by requiring less in the tub for each load.
You can also reduce dryer energy by 10 to 20% by using the new appliances designed for energy efficiency. Look for the ENERGY STAR label to ensure that you're getting models with the best energy efficiency.
If you have Solar PV cells or a Solar Thermal system...run your wash in the afternoons with solar hot water and solar power!
You can also save energy by hanging your clothes to dry. Indoors. Outdoors....take your choice...they are both zero energy options!
Energy Star Dishwashers
If you're the kind of cook who absolutely refuses to wash your dishes in the sink -- which is far more energy and water efficient than an appliance -- be sure to select the highest efficiency model using Energy Star rating. Look for the Energy Guide label.
Where you place your dishwasher and clothes washer can also save you money. By keeping the (Insulated pipes, of course!) plumbing lines to the waer heater SHORT, you save temperature cooling. And consider designing your water heater close to both kitchen and bathrooms for greatest building and energy economy!
Designing your energy and water infrastructure for efficiency is step one in energy savings. Nothing can make up for large houses, long distance plumbing, or inefficient applieances. And you can end up paying many times the initial cost of the construction in your rising energy bills! Think ahead to save for years to come.
Zero Energy Homes are also high comfort homes! Food preparation leads to the kitchen being the MOST important room in the entire house, and food choices are just part of the energy equation. Yes, organic food benefits the environment and your taste buds...and you health. But what you store that food in is a BIG contributor to your energy consumption.
Refrigerators are energy hogs...and that sucks the bacon right off your plate! :-)
When you remodel your kitchen, or decide it's just time to replace your refrigerator consider recycling your old refrigerator in a responsible way. Call your local public utility company or your city solid waste department to see if they have a refrigerator recycling program. By recycling this equipment, the toxic chemicals in the cooling system can be reclaimed and kept out of your community's drinking water supplies...and the metal can be recycled to prevent further damage to your environment.
But...back to the point of this article...how do you save energy with a new refrigerator?
By the most efficient refrigerator of the size and type that best fits your needs. Don't supersize it! And resist the urge for a second frig and separate freezer. Bulk saves energy!
Refrigerators with top freezers are the most efficient. And by turning off the moisture control, you can save more! If you live in a low humidity, temperate climate zone (like California), you really don't need that little heater running all the time because moisture just isn't a problem. And you'll save on your electric bill!
Refrigerators are energy hogs...and that sucks the bacon right off your plate! :-)
When you remodel your kitchen, or decide it's just time to replace your refrigerator consider recycling your old refrigerator in a responsible way. Call your local public utility company or your city solid waste department to see if they have a refrigerator recycling program. By recycling this equipment, the toxic chemicals in the cooling system can be reclaimed and kept out of your community's drinking water supplies...and the metal can be recycled to prevent further damage to your environment.
But...back to the point of this article...how do you save energy with a new refrigerator?
By the most efficient refrigerator of the size and type that best fits your needs. Don't supersize it! And resist the urge for a second frig and separate freezer. Bulk saves energy!
Refrigerators with top freezers are the most efficient. And by turning off the moisture control, you can save more! If you live in a low humidity, temperate climate zone (like California), you really don't need that little heater running all the time because moisture just isn't a problem. And you'll save on your electric bill!
Cooling Systems
Whole House Fan or Economizer System
The principal of ventilation cooling is to circulate cool night air through buildings, thereby cooling (removing heat from) interior mass surfaces such as walls, concrete floors, and furnishings. During the day this cool mass absorbs heat from the air, keeping indoor temperatures more comfortable. Studies have shown that ventilation cooling can eliminate the need for air conditioning in coastal California climate zones, and can substantially reduce both total and peak demand air conditioning energy use in the inland valleys.
One example is:
Whole House Fan or Economizer System
The principal of ventilation cooling is to circulate cool night air through buildings, thereby cooling (removing heat from) interior mass surfaces such as walls, concrete floors, and furnishings. During the day this cool mass absorbs heat from the air, keeping indoor temperatures more comfortable. Studies have shown that ventilation cooling can eliminate the need for air conditioning in coastal California climate zones, and can substantially reduce both total and peak demand air conditioning energy use in the inland valleys.
One example is:
Davis Energy Group: Nightbreeze is an integrated night ventilation cooling system with intelligent adaptive controls that optimize security, cooling comfort and energy: www.davisenergy.com.
Auxiliary air conditioning should have a minimum of SEER 17. Building codes require a minimum of 13.
To maximize savings, consider advanced systems with SEER 18+ that come with high speed operation disabled. Also, evaporatively cooled condensers in hot locations are an option that work like air conditioners, but they accept outside air that is cooled by evaporation.
Heating Systems
Fully condensing gas furances (91%+) are highly efficient. Tankless gas heaters with hydronic loop, connected with a whole house economizer system (Nightbreeze, Rinani, Tacagui) are also efficient. If you use an electric heat pump, consider geothermal ground loop system and minimize circulation pump power.
When the wind blows, temperatures fluctuate -- we know that is normal in nature, but we forget that we've domesticated air to blow through ducts. But we can significantly improve energy use if we put some thought to how our home ventilation is designed and insulated.
Ducts placed in conditioned space formed by a false ceiling can have a 10% influence on heating and cooling costs.
If it's not possible to create this conditioned space for your duct system, consider burying your ducts in deep ceiling insulation and seal the attic with roof deck insulation.
Ducts in unconditioned attic space can lose up to 1/3 of the energy used to condition the air inside the ducts.
Ductless heat pumps can also be an alternative.
Ducts should be well-sealed and tested; smooth round ducts are more efficient than flex ducts because they provide lower friction and thus, require lower fan power.
Ducts placed in conditioned space formed by a false ceiling can have a 10% influence on heating and cooling costs.
If it's not possible to create this conditioned space for your duct system, consider burying your ducts in deep ceiling insulation and seal the attic with roof deck insulation.
Ducts in unconditioned attic space can lose up to 1/3 of the energy used to condition the air inside the ducts.
Ductless heat pumps can also be an alternative.
Ducts should be well-sealed and tested; smooth round ducts are more efficient than flex ducts because they provide lower friction and thus, require lower fan power.
Ceilings
Ceilings provide many opportunities for insulating against severe temperatures. Most ceilings are exposed to the attic, and often, attics are not as insulated or ventilated as they could be. If attics are seen as tools in the zero energy process, they can be managed to moderate temperatures before those heat or cold fronts affect room ceilings.
R-38 insulation in warm climates and R-49 in cold climates, coupled with advanced framing techniques are your first rung of ceiling defense.
Ceilings above and below need to be inspected for consistency and gaps in insulation. Ducts should be buried in insulation if they are part of the attic landscape.
Garages are often poorly insulated, again considered secondary space, similar to attics. But any space next to living space conducts temperatures through surfaces to adjacent living spaces -- so garages should be well insulated in hot climates to reduce energy use.
Roofs
Start with the shape of your roof -- pitched roofs have larger areas and the steeper the pitch, the more material, time and upkeep will be required for the roof itself. Then comes insulation of the added space!
Hot climates benefit from special attention to roofing materials and insulation. Light colored tiles with a radiant barrier underneath; or light colored metal make good choices for energy efficient roofs.
Insulated roof decks benefit from at least R-30 coupled with light colored tile that is well sealed.
Ceilings provide many opportunities for insulating against severe temperatures. Most ceilings are exposed to the attic, and often, attics are not as insulated or ventilated as they could be. If attics are seen as tools in the zero energy process, they can be managed to moderate temperatures before those heat or cold fronts affect room ceilings.
R-38 insulation in warm climates and R-49 in cold climates, coupled with advanced framing techniques are your first rung of ceiling defense.
Ceilings above and below need to be inspected for consistency and gaps in insulation. Ducts should be buried in insulation if they are part of the attic landscape.
Garages are often poorly insulated, again considered secondary space, similar to attics. But any space next to living space conducts temperatures through surfaces to adjacent living spaces -- so garages should be well insulated in hot climates to reduce energy use.
Roofs
Start with the shape of your roof -- pitched roofs have larger areas and the steeper the pitch, the more material, time and upkeep will be required for the roof itself. Then comes insulation of the added space!
Hot climates benefit from special attention to roofing materials and insulation. Light colored tiles with a radiant barrier underneath; or light colored metal make good choices for energy efficient roofs.
Insulated roof decks benefit from at least R-30 coupled with light colored tile that is well sealed.
Glass windows are important for mental health and connections to the environment that surrounds us, but they also can be an energy drain as uncontrolled sunshine or cold winds penetrate into the building through these thin, hard surfaces. Here are some methods to reduce energy use through windows:
- Use high performance solar control windows designed for your climate. Insulated frames are better in some situations, non-metal frames in other.
- Attempt to orient your window spaces more to the south, with awnings to protect during summer heat.
- Aim for glass to floor area ratio of 15% or less.
- Add 2 - 3 foot overhangs on south facing windows in warm climates
- Use old-fashioned porches to protect windows and doors from weather -- sun, rain and heat
Zero Energy Homes are constructed (or remodeled) to reduce the amount of energy and balance usage with renewable energy generation. Here are some of the successful strategies that maximize energy conservation:
- Cut total electrical loads to 15 kWh per day
- Think less house, more efficiency, just say NO to McMansions
- Add 3-4 kW solar PV system with inverter to generate 15 kWh/day
- Effective solar water heating system with tankless gas water heater auxiliary
- Solar control measures to reduce air conditioning with good insulation, porches, reflective surfaces, and trees
- Well insulated building to reduce heating loads
- Use Energy Star rated appliances of all types: refrigerators, dishwashers, washers, televisions, computers
- Monitor real time energy use to guide your successful identification of key problem areas.
Exterior walls provide large surfaces that are exposed to the elements and interior walls can become tunnels of air in through interior spaces.
Energy conservation with wall construction provide a variety of options such as:
Energy conservation with wall construction provide a variety of options such as:
- Minimum R-19 insulation
- Inspect insulation to eliminate gaps that result from remodels or settling insulation
- Consider advanced framing or insulated headers
- R-10 exterior sheathing can prevent thermal bridges
- Light pastel paint colors in hot climates can reflect heat on exterior walls
- Green walls or trees outside West windows can also provide shade to reduce hot afternoon temperature rises
Sunshine is hot...water needs to be heated....whalah...combine them!
Solar Water Heating System
Solar water heating can use an Integrated Collector Storage system to preheat water. And solar water heaters are now eligible for some nice incentives in some states such as California.
Integrated Collection Storage systems (ICS) are best where there is no freeze danger.
You will get better performance from open look, active systems with a 40 square foot cllector and DC solar powered pump (for simple operation)
You can use a tankless gas backup for 77% efficiency.
What to watch for...beware of hot water recirculation systems without occupancy control. On demand systems can increase energy use by 3X. Ask your local utility company for their input on the best system configurations.
Solar Water Heating System
Solar water heating can use an Integrated Collector Storage system to preheat water. And solar water heaters are now eligible for some nice incentives in some states such as California.
Integrated Collection Storage systems (ICS) are best where there is no freeze danger.
You will get better performance from open look, active systems with a 40 square foot cllector and DC solar powered pump (for simple operation)
You can use a tankless gas backup for 77% efficiency.
What to watch for...beware of hot water recirculation systems without occupancy control. On demand systems can increase energy use by 3X. Ask your local utility company for their input on the best system configurations.
Floors are important surfaces for energy transfer because of their proximity to the bare earth or air spaces. Reducing loss of heat and cool in rooms -- and reaching zero energy requires effective material choice for the climate, and proper insulation of these large surface.
Tile Floors
Tile floors work best in hot climates and offer free cooling with up to half a ton of savings in early summer. Throw rugs can be used for comfort during winter to insulate room temperatures from the cooler floor temperature.
Floor Insulation
Use R-5 perimeter insulation around the edges of the slab on grade construction to protect the floor from ground temperatures. And for raised, wooden floors, insulate crawlspaces with R-30 floor insulation.
In cold climates, carpet adds comfort to the room because it provides a layer of insulation, whether you have wood or slab flooring.
Tile Floors
Tile floors work best in hot climates and offer free cooling with up to half a ton of savings in early summer. Throw rugs can be used for comfort during winter to insulate room temperatures from the cooler floor temperature.
Floor Insulation
Use R-5 perimeter insulation around the edges of the slab on grade construction to protect the floor from ground temperatures. And for raised, wooden floors, insulate crawlspaces with R-30 floor insulation.
In cold climates, carpet adds comfort to the room because it provides a layer of insulation, whether you have wood or slab flooring.
