ENERGY EFFICIENCY

At Solar-Ray, we believe energy efficiency is an important aspect to a successful solar power program. Undoubtedly, it is in this area that Americans can make the largest impact toward a more sustainable energy future. There are many simple and cost-effective measures that can be taken to use less energy with little or no affect on current lifestyles. Combined with a well-designed solar-electric system, it can bring you that much closer to a zero-carbon footprint.

Below is a list of common suggestions that will help you use less energy. We have also included links to several excellent resources on the web that are dedicated to energy conservation.

In the Home

• Use compact fluorescent light bulbs. A three-dollar CFL bulb can save you up to $50 in energy cost over the life of the bulb. They last 10 times longer than standard bulbs and provide excellent, quality light while reducing energy use by two-thirds.
• Install a programmable thermostat for your air conditioner and heater. This allows you to automatically adjust to the most efficient setting throughout the day and night. The energy savings would more than pay for the new thermostat.
• Increase your attic insulation to R30. Adding insulation to the attic is relatively easy and very cost effective. You can consult a reputable insulation contractor to determine what your home needs or learn how yourself with this information from the U.S. Department of Energy.
• Make sure all doors and windows are properly sealed. Air infiltration can account for 30% or more of a home’s heating and cooling costs. Follow this link for more tips from the U.S. Department of Energy.
• Check the filter on your air conditioner regularly and change when necessary. Filters can quickly fill with dust blocking important air flow that will reduce the system’s efficiency.
• When not in use, turn off electronic devices that use standby power. Use a power strip to conveniently turn off several electronic devices such as computers, printers, cell phone chargers, DVD players, etc. The transformer in an AC adapter, or built-in standby power systems, draw power continuously, even when the device is not in use.
• Use ceiling fans.Two fans, rather than an 8,000 BTUH room air conditioner running four hours a day, will save over 1,150 kWh and $161 per year.
• When buying new appliances, choose those with the Energy Star designation. Energy Star is a government-backed program helping businesses and individuals protect the environment through superior energy efficiency. Appliances with this label usually exceed minimum federal standards by a substantial amount. To learn more about the Energy Star label, visit their website here.
• Use energy saving devices in your outdoor lighting design. Use a photocell unit or a motion sensor so outdoor lights will turn on only at night or when someone is present. There are also several varieties of solar-powered lights for lawn and walkways that work efficiently.
• Install a solar or point-of-use hot water heater. With current rebates and tax incentives, a solar water heater is one of the best investments you can make, financially as well as for the environment. If your home does not have enough solar exposure, consider an on-demand or tankless system. Research has found savings can be up to 30% compared with a standard water heater.

For additional information please visit the U.S. DOE’s Consumer Guide to Energy Efficiency and Renewable Energy.

New Construction and Home Renovations

If you are planning a new home, first orient the building to maximize north and south exposures. Then:

• Minimize glass on the east and west, especially the west.
• Properly size overhangs so there is no sun penetration during the summer equinox (21 June) on the southern exposure. The size will depend on the location within the state and height of the windows. For the Orlando area, it is ten (10) inches for a window four (4) feet high and the overhang located nine (9) inches above the top of the window. For floor to ceiling windows or patio doors (standard ceiling height), it is approximately 18 inches.
• Select windows that will help manage heat gain and losses. For example, use low-e glass with very low SHGCs for east and west orientations and high SHGCs for the southern exposure. You can take advantage of the solar benefit during the winter months by using some passive solar design. And, remember, skylights do add to the cooling load.
• If your view is to the west, consider using a wide covered porch in order to reduce solar heat gain in the living spaces.
• Consider insulating the inside of your exterior walls so that the wall can serve as a heat storage medium. What heat does not get into the building will not need to be cooled.
• If you take advantage of the benefits of passive solar design, remember that concrete block walls and darker clay tile floors are great storage media and will help level your heating and cooling loads throughout the year, thereby, reducing utility bills.
• Consider a whole house fan design for natural ventilation. Wing walls will also facilitate use of natural cooling.
• Try to keep ductwork within insulated spaces and seal the ducts well.
• If your home has substantial thermal storage capacity, night setback thermostats will not save much energy.

For those planning major renovations, many of the above considerations are also relevant.

• If you plan to change your windows, consider using low-e for Southern climates. For east and west windows, select those with low Solar Heat Gain Coefficients (SHGC). Select operable windows in order to take advantage of natural ventilation during late fall, winter and early spring.
• For both new construction and renovation, it is important to design the building as an integrated system. There is no one rule that will provide the most energy efficient building. It is the combination of design and equipment/appliance features and living styles that determine the building’s performance.
• Do not oversize the heating and cooling equipment. Oversized systems are inefficient and will increase the utility bills.
• Sunrooms: It is recommended that glass not be used in the roof. Such glass adds a significant cooling load. Further, the sunroom ought not be oriented to the west or east. A southern orientation with properly sized overhangs is ideal for year round use and minimal additional heating and cooling requirements. By adding thermal storage to south-facing sunspaces, the solar heat gained during the winter months can provide significant heating.
• Landscaping: Consider deciduous trees on the east and west sides of the buildings. They will help shade the building from the sun. Fruit trees can be used.

References: Sustainable Buildings Industries Council publications and design tools. See web site at www.sbicouncil.org. For a simple tool, the Builder Guidelines are very helpful.

Florida Solar Energy Center references on natural cooling design strategies: www.fsec.ucf.edu

Information sources: U.S. Department of Energy, Florida Power and Light