STEP 1: Evaluate and Lower Your Energy Use
The first step to designing your new renewable energy system is evaluating your current power use and where you can conserve. This will translate into cost savings when you are ready to buy.
Click to see our list of 53 No-Cost and Low-Cost Ways to Conserve Energy.
Start by pulling out your electric bills and calculate the average Kilowatt Hours (kWh) for both the winter and summer seasons, and make a note of your highest energy use. Your utility company may already have these calculations available through your online account, or give their customer service a call. These are key figures to help determine the size of your solar electric system.
If cost is not an issue, or if you are already saving energy with a sustainable green lifestyle, you can skip the following information and move to Step 2: Decide What Kind of System You Need.
Further evaluation of your current energy use may reveal exactly where you can be more energy and cost efficient, ultimately making the best use of your solar PV system. See our pie chart and power consumption table for typical household percentages and hourly watts of individual appliances, lights and other electrical equipment. See how to calculate daily energy use with our Load Evaluation Worksheet and the refrigerator example on the right.
As each individual within your household has a different lifestyle and habits, your use of electricity may be very different than the averages. A Kill-A-Watt meter can easily show you exactly how much energy you are using on most items.
Your utility or local government programs may be a great resource for your energy saving plan (and cost saving incentives). They may have free or low cost programs for evaluating your energy use and where your home may be loosing energy through ducting, walls and windows, etc. Some of these programs may have websites than can help you keep track of your energy consumption on an ongoing basis as well.
You may want to take advantage of 'Smart Home' computer programs or companies. Some programs are set up to alert you when an appliance or zone of your home is using more electricity than it should. These energy management technologies can be as simple as allowing you to open or close your garage door from a phone app, to highly sophisticated (though often expensive) whole house control and automation.
Ways to Conserve Energy
If you need to save some time, you can skip down to our list of steps you can take to lower your energy use.
Reduce Phantom Loads
Phantom loads refer to when appliances continue to draw electricity when they are "off" or in the "standby" position. They can draw electricity 24 hours a day, and some appliances draw close to full power just to be on standby. Common examples include:
- Glow bars in gas ovens
- Electronic phones
- Anything with a small "box" on the power cord
Energy Efficient Lighting
Besides changing all of your bulbs, there are other things you can do. Use daylight for reading, working and living. Low wattage task lighting can replace high-energy general overheads. Lighter colors on the walls reflect more light, and solar tubes or skylights can be an added improvement to darker areas.
New higher efficiency standards for light bulbs were put into law through the Energy Independence and Security Act of 2007 (EISA) and became effective nationwide January 1, 2012. Most bulbs are required to be 25% more efficient by using less energy in watts to produce the same amount of light, measured in lumens.
New Energy Star labeling will show lumens, estimated yearly cost, expected life, color, and watts. Look at the lumens for the brightness you want, and watts for the amount of energy that is used. This will ultimately make it easier to choose between types of bulbs.
The traditional 100-watt incandescent bulb is being replaced by a 72-watt incandescent halogen bulb, which emits about 1,600 to 1,700 lumens. Compact fluorescent bulbs that emit the same lumens only use 23 watts. While the more efficient incandescent bulbs are less expensive, the energy savings of compact fluorescent or LED bulbs more than pay for initial higher costs.
Compact fluorescent bulbs will typically save $3/year per replaced bulb (when used 4-6 hours per day). CFL bulbs can last up to 10 times longer than conventional incandescent bulbs.
LED (light-emitting diode) bulbs provide an optimal light color that is equal to or better than incandescent. LED bulbs are more durable and will not break as easily as incandescent or CFL bulbs. LED is initially more expensive than CFL but can last up to 5 times longer than CFL.
Both CFLs and LEDs use about 75 percent less energy than incandescent bulbs, without sacrificing any light. They also generate very little heat. Look for Energy Star rated bulbs for the best warranties and longest lasting lights. For instance, in about a year, lower quality LEDs can become dim and uneven, flicker, shift in color, or continue to use power when turned off, among other issues.
How to Cut Heating Costs
1. Insulation - One of the most cost-effective ways to make your home more energy efficient and comfortable is to add insulation. An under insulated attic may be the largest source of energy loss as heat rises up and through the ceiling, into and out of the attic. Walls are the second place heat looks to escape, especially in older homes where insulation could be worn or settled, or simply not insulated. Insulated window blinds or curtains can also help contain heat at night. Remember even double pane windows have very little insulative value. Click here for more information about how to use insulation with passive solar.
2. Seal air leaks. Sealing air leaks to keep the cold air out by adding storm windows or caulking gaps around the outside of windows will stop the draft from entering your insulated home.
3. Use setback thermostats. These can be installed and programmed to lower household temperatures according to your needs. You can also manually setback your thermostat. By lowering room temperatures by five degrees for an eight to twelve hour period, you can save five percent on your heating bill.
4. Use passive solar techniques. Passive Solar techniques capture the sun's energy to warm your home and avoid capture of the same energy when it is necessary to keep the house cool. House design that takes into account the changing angle of the sun, from winter to summer, can dramatically lower your energy costs.
Lower Water Heating Costs
Water heating is a major energy expense in a home. It usually accounts for 13% of your utility bill. There are six ways to reduce your water heating energy consumption:
1. Insulate the water heater. You can save money by wrapping your gas or electric hot water heater in an insulative jacket. Wraps are readily available at hardware stores and can be installed by the homeowner.
2. Lower water heater thermostat. Lower the thermostat to 110 degrees F, to optimize efficiency. And if you have an electric water heater, a timer can be installed to regulate heating cycles.
3. Insulate pipes. Too much heat is lost from the pipes coming directly from the hot water heater, and even more is lost in unheated crawl spaces. Pipe insulation greatly reduces heat loss in these areas. Users will spend less time waiting for hot water at the tap, and it will lead to less waste. On demand hot water circulation is an exciting innovation in this area and can maximize efficiency.
4. Install aerators at the faucets. These reduce hot and cold water flow while maintaining the original water pressure.
5. Install low flow showerheads. These help reduce water use by up to 50 percent.
6. Use less hot water. The 15 percent of energy that used to heat water in an average home can be lowered considerably by using a simple formula of insulating and conserving. By maximizing household efficiency, you will save.
Energy Star Appliances
The laundry area and kitchen of the modern house contain the biggest users of electricity. If energy is conserved and use of Energy Star appliances is maximized, your home is well on the way to becoming an example of independent living. Click here for a list of how much power each appliance uses.
Consider your appliances and how you use them. In general, side-load washers use less energy than top-load washers. Many food preparations can be done without electricity, and meals can be cooked alternatively with a Dutch oven, pressure cooker, or toaster oven, and three dishes baking at once save the cook's time and conserve energy too.
Energy Efficient Refrigerators
Refrigerators are infamous for using way too much energy. If your existing refrigerator is over 10 years old, replace it with a new energy efficient refrigerator. Newer models are much more energy efficient than the old avocado green refrigerator at grandma's house. New refrigerators don't have to be expensive to be efficient. Check the Energy Guide stickers as well as the price tags. And last but not least, consider a smaller unit because, with refrigerators, bigger is not better.
If replacing your old unit with a modern high efficiency model is not an option, keep your old fridge tuned up by cleaning the ventilation grilles and giving it some room from the wall to allow for ventilation. Use the energy saving feature, if available, or set the thermostat to the minimum requirement of 38 degrees. Keep your freezer as full as possible. Use plastic bottles filled with water for empty spaces.
STEPS YOU CAN TAKE TO LOWER YOUR ENERGY USE
25 No Cost Steps
These easy steps can potentially lower your kWh usage by 10-25%.
- Unplug items you rarely use.
- Unplug your televisions/VCR, stereos, clocks, cordless vacuums and small appliances when you're away on vacation. Many items draw power even when they're turned off.
- Turn off lights and appliances when not in use. Remember to turn off your computer, or use the sleep setting.
- Turn down the brightness on your TV and computer monitor.
- Keep lights and lighting fixtures clean, especially if you're reducing the number of lights you use. Dirt absorbs light. Let lights cool before cleaning them and never touch halogen bulbs with your bare hands. The oil from your skin can greatly damage the bulbs. Use a small piece of paper to hold the bulb.
- Dress according to the weather and the season.
- Close foundation vents in the winter months.
- If your air conditioning unit is on the ground, keep the area around it clean and free of obstructions to maintain airflow. Vacuuming A/C and furnace filters can help increase efficiency between filter replacements.
- Set or program your thermostat according to the season: for hot/warm months, 78-80 degrees when home and 5 to 10 degrees warmer when you're away; in cold months, set the thermostat to 68 degrees when home, and lower to 55-62 degrees when leaving the house.
- Take full advantage of your window coverings. In the summer, close blinds and drapes during the day to keep heat out. In the winter, open window coverings on the sunny side of your home to take advantage of free heat from the sun. Close the coverings on cloudy days or right after the sun sets.
- Use your dishwasher, clothes washer and dryer as late in the evening as possible, especially in summer months. (This is still true when you have a solar PV system, and you are using supplemental energy from the grid. If you are completely off grid you may want to live without a dishwasher and do your dishes by hand. As much as possible, everyone with solar PV systems and battery backup should wait until after 2pm when your battery bank is full and the sun is still up to run these appliances using the PV panel generated electricity.)
- Run full loads in your dishwasher, washer and dryer. Use cold-water to wash clothes as much as possible (90% of energy is used to heat the water).
- Use the energy saver option on your dishwasher, allowing dishes to air dry. If your dishwasher has a filter, keep it clean.
- Clean the dryer lint filter with each load.
- Clean the dryer ducting periodically to increase efficiency and prevent a fire hazard from accumulated lint.
- Utilize a clothesline for drying your clothes.
- In warmer weather, barbecue outdoors when practical, or cook later in the evening. Reducing the heat coming into your home from any source, such as cooking, will reduce the load on your air conditioning. (A/C uses more energy than is really practical if you are completely independent off grid. Using a swamp/evaporative cooler, if ample water is available, and/or as many Passive Solar techniques as possible is critical for off-grid living in hot climates.)
- Clean the reflectors underneath the burners on stovetops.
- Make sure food is cool and covered before it goes into the refrigerator.
- Use the energy saving feature on your refrigerator, if available, or set the thermostat to 38 degrees.
- Keep your freezer as full as possible. Use containers or plastic bottles filled with water for empty spaces.
- Vacuum refrigerator and freezer coils (underneath and in the back) and don't obstruct the coils. They need air space to work.
- Keep the seals (gaskets) on refrigerators and freezers clean.
- Turn off the water while you brush your teeth at the sink and while you are soaping up and washing your hair in the shower.
- Set your water heater to 110 degrees.
These easy steps can save you 10-25% of your energy usage.
- Install electrical outlet and switch plate insulation.
- Change your incandescent bulbs to Energy Star rated compact fluorescent bulbs (CFL's) or light-emitting diode bulbs (LEDs). Both radiate less heat and use about 75% less energy than incandescent bulbs.
- Use smart power strips for your home theaters and entertainment centers that will prevent your game players or stereo from using power when you are only watching TV.
- Replace worn or damaged seals on your refrigerator and freezer.
- Install a door sweep at the bottom of your door between your home and your garage to seal the gap and prevent cold air from coming in and warm air from escaping your home.
- Caulk windows and exterior doors.
- Seal small gaps around plumbing stacks, vents, ducts, or electrical wires with caulk and seal holes up to 3 inches in diameter with spray foam. For spaces larger than 3 inches, cover with a piece of foam board and seal with spray foam.
- Install a water heater blanket but be careful not to cover vents or temperature settings.
- Install hot water pipe insulation. Keep the insulation at least six inches away from the flue (exhaust pipe) of gas water heaters.
- Fix leaky faucets.
- Install low-flow showerheads and faucet aerators.
- Use room fans to keep the air moving and reduce the feeling of heat in your home.
- Replace furnace and air conditioner filters at least once a year. Check filters every 30 days and replace if necessary. Spray the filters with a light coating of lemon furniture polish or vegetable oil cooking spray to help trap dirt in the filter.
- Seal holes, tears and leaking connections of HVAC ducts using mastic or metal (foil) tape (never use 'duct tape,' as it is not long-lasting).
- Seal holes and gaps around chimneys or furnace flues that penetrate your attic floor. At areas that get hot use metal flashing for larger gaps and use high temperature caulk for small holes and gaps.
- Replace normal thermostats with programmable thermostats.
- Install pool trippers to reduce the time your swimming pool pump runs. 8-12 hours a day is sufficient.
- Buy a cover for your pool to retain heat in the water.
- Plant trees and shrubs on the south and west side of your residence. The vegetation acts as insulation and provides shading, reducing thermal gain in a building.
9 Added Cost Steps
These steps could potentially save you another 25% on your kWh used.
Remember to do your research before you sign a contract or put down a deposit.
- Install floor and ceiling insulation: It is recommended to have a minimum of an R-30 - R-38 insulation in the attic (varies per climate) and R19 insulation in the sub-floor. (Find and seal air leaks before adding more insulation.)
- Add window screens or window films to reduce the solar energy from entering your home. Remember to include skylights; some shade systems include remote controls making them more convenient to operate.
- Replace inefficient and single pane windows with energy efficient multi-pane, thermally-broken, vinyl-framed windows. Windows with integral solar blind systems may qualify for the 30% Solar Federal Tax Credit.
- Appliances over 10 years old are usually not as energy efficient as newer models. Look for products with the ENERGY STAR™ label. The Energy Guide Label tells you how efficient it is and how much it will cost you to run.
- Service your heating and air conditioning systems once a year.
- If your furnace is over 10 years old, replace with a 90%, or greater AFUE (Annual Fuel Utilization Efficiency) rated unit.
- If your centralized air is over 10 years old, replace it with a properly sized unit for your home. Oversizing or under sizing your AC unit can reduce efficiency, accelerate wear, and shorten its lifespan.
- Testing and sealing the ductwork. Not only does this improve the efficiency of your heating and cooling system, it makes the house more comfortable.
- Have ceiling fans installed in all bedrooms and your family room. They can make you more comfortable while allowing you to set your thermostat to higher temperatures in the summer and lower temperatures in the winter.
2005 Buildings Energy Data Book, Table 4.2.1., 2003 energy cost data.
Energy Conservation Primer, Coleman, Mark and Burlin, Will. 20 page pdf file, pgs. 7-14.
Energy Savers, U.S. Department of Energy EERE, 34 page pdf file, pgs. 15-16, 20, 24.
US Environmental Protection Agency (EPA) Energy Star Website