January 6, 2010

energy efficient houses nearby: Willet Family, Ft. Pierce, FL

There are many reasons to build an energy efficient house but the most persuasive is the realization that the electric grid on which we depend is itself dependent on forces outside its control. Several independent minded homeowners have installed photovoltaic systems so that solar energy can run some or all of their electric appliances. From time to time, one of these homes will be featured here.

Willet Family: a family home of over 4,000 sq.feet with a 18ft x 50ft. heated pool.

year built: 2001

Power Source: 24 solar panels plus panels to heat pool plus a battery bank to back it up as well as a 20 kw LP gas generator.
---Solar system runs indoor lights, microwave oven, refrigerator, washer, outlets, ceiling fans. Pool pump and heat is solar. Also, 120 gallon hot water tank is solar
---FPL's power grid runs other major systems
---Battery back up supplies the indoor lights, microwave over, refrigerator, washer, outlets, and ceiling fans as needed. The batteries are of the sealed variety to reduce maintenance. They require a ventilated space.

Building envelope: Walls are Insulated concrete block (ICF) reinforced with rebar horizontally and vertically every four feet. Insulation rating - R-30. Metal lathe on outside/ stucco/ elastic merit paint (usually used on commercial buildings, but is great at keeping water out.)
--Roof has waterproof membrane/ vinyl soffits with extra caulking and screws to hold them in place. Metal roof trusses (rather than wood)
Floor of attic is 1 inch blueboard/ 1/2 inch plywood/ 1/2 inch sheetrock. This allows workmen to walk in the attic.
--Windows: hurricane windows plus shutters. However, low-e glass was not available in a hurricane window at the time house was built.
--Soundproofing: 5/8 inch sheetrock and fiberglass between walls.

Insulation: closed cell spray foam/ attic insulation R-40

Water: all main lines are 1 inch pipes
--has city water and well water backup
--filters city water to remove chlorine, etc. Also, softens city water.
--All water pipes - hot and cold - are insulated.
--recirculate hot water so that it will be available throughout system.
--perimeter of house has trench filled with pebbles and pipe to drain water away from the foundation

Air conditioning system: Lennox units with 2 stage compressor
--variable speed a/c
--humidistat
--piped to drain water out of building
--media filter with ultraviolet light to prevent mold and dust build up in ducts and on coils
--ceiling fans everywhere

Options: whole house surge protector
--central vacuum
--prewired sound system
--wired for computers and cable tv
--switches on all appliances to cut energy drain

Regrets: putting in a skylight and a solar tube as they are too expensive and created a break in the roof.

Resources: Home Power http://www.homepower.com/ / Solar Today http://www.solartoday.org/


What do you call a ....

New interests almost always challenge us with a new vocabulary. Think of all the terms particular to baseball - home plate? outfielder? high and inside? - ??? Consider the words special to your gardening project - mulch? prune? nematode?. You see what I mean.

In renovating a house so that it is "green" (that's the first new word; it is overused), you will be introduced to many new words. Here is a list of just a few to start. We'll learn more as we go along.

conditioned-space: A space in which an HVAC system supplies conditioned air to produce acceptable thermal comfort and indoor air quality conditions.

cool roof: A roofing system (often metal) with high solar reflectance (reflecting visible, infrared, and ultraviolet light) and high thermal emittance (releasing a large percentage of absorbed and non-reflected, solar energy). This reduces heat transfer to the building and energy needed for cooling.

dsire (Database of State Incentives for Renewables and Efficiency): provides state by state info on tax credits and rebates. http://www.dsireusa.org/

energy star: A joint program of the US Environmental Protection Agency and the US Dept. of Energy begun in 1992. It helps consumers identify energy efficient products and also identifies tax credits. http://www.energystar.gov/

HERS : a scoring system established by the Residential Energy Services Network which compares the energy use of a home to a reference home. The reference home has a score of 100; a zero energy home scores "0".

green power: A source of regenerative or virtually inexhaustible energy considered to be non-polluting and environmentally friendly.

green roof: A roof that is partially or mostly covered with vegetation and soil (or a growing medium), planted over a waterproofing membrane. Such roofs reduce heating/cooling loads. Also called eco-roofs, vegetated roofs and living roofs.

green wash: To falsely claim a product is environmentally sound.

HVAC: A term generally used to describe a buildings' comfort system. In older buildings, heating (radiators), ventilation (windows), and air conditioning (window units) may be separate, but usually these services are integrated into a single system that conditions air throughout the zones of a building.

icynene: a spray foam insulation with superior air sealing capabilities. Qualifies for the Home Improvement Tax Credit up to $1500.

inverter: A device that converts Direct Current (DC) generated by solar panels to Alternating Current (AC) used in homes.

low-e: also "low emissivity": Windows with special coatings that transmit most of the sun's light but block heat radiation from passing through.

Out-gas: The emitting of fumes into the air that are unpleasant to breathe and may be hazardous to occupant health. Many new paints, carpeting, sealants, adhesives, and other building materials will do this for a time after installation.

overhang: A projecting part such as an architectural structure.

photovoltaics: A solar power technology consisting of devices or an array of devices that convert light into electricity.

post consumer: material taken from used consumer products that is used again, e.g. paper, cardboard, wood, stone, concrete, glass.

recycle:
To extract and reuse useful substances from waste; to use again; to reprocess

renewable: relating to a natural source which is never used up

renewable energy: also "green power" and "alternative energy" A source of regenerative or virtually inexhaustible energy considered to be non-polluting and environmentally friendly, such as geothermal, wind, water, biomass, and solar power

seer (Seasonal Energy Efficiency Ratio): A measure of the efficiency of air conditioners with the BTU of cooling output during its normal annual usage divided by the total electric energy input in watt-hours during the same period. The higher the number, the more efficient the device.

sustainablity: improving the quality of human life while living within the carrying capacity of supporting eco-systems"

Definitions come from online dictionaries and the Green Building and Controls Glossary from KMC controls. Thank you!