Why Passive Solar?
The vastmajority of buildings ignore numerous energy-saving opportunities - opportunities that blend natural elements, such as sunlight, breezes, and landscape features with energy efficient building materials and techniques. Passive solar design strategies use the standard elements of a building - walls, windows, and floors - to collect, store, and release the sunís energy for heating, lighting, and cooling. By applying these time-tested strategies, a buildingís energy consumption can be dramatically reduced - for little or no added cost - while improving comfort, energy, economic and environmental performance. Passive solar design decreases the need for purchased energy.
Passive solar relies entirely on careful design and construction. It does not require specialized equipment to take advantage of the natural principles of how energy moves in a structure. While a passive building doesnít necessarily look different from itís "conventional" next-door neighbor, it performs far better because it uses high quality materials and products in a more energy-conscious way.
- Taken from the "Passive Solar Industries Council" web site: http://www.psic.org
What is "Net Metering?"
Net metering became the law in Nevada in 1997, allowing customers to "run their meter backward!" Net Metering allows residential and commercial customers to generate their own wind or solar electricity, and apply any excess electricity generated as a credit toward their utility bill, up to one year. Nevada is one of nineteen states which require utility companies to allow customers the opportunity to generate electricity by installing their own solar or wind systems. Net metering will reduce your utility bill, contribute to a clean environment, and help utility companies meet our future energy needs.
- From the Independent Power Systems brochure. Call (702) 331-0228 for more information.
For an example of net metering, see the Barritt Home, the first net metered house in the State of Nevada.
What is "Photovoltaics," and how can sunlight be used to generate electricity?
Photovoltaics, PV, or solar cells are generally silicon crystals, which start out very much like the technology that makes microchips for computers. Silicon has the wonderful property of producing a flow of electrons (electricity) when sunlight strikes its surface. Technically, when "packets" of sunlight (photons) hit the silicon wafer, electrons are dislodged, and these electrons are free to flow to small wires embedded on the silicon crystal. This electron flow creates electricity. A single crystal produces just under 1/2 volt, but they can be connected in series to produces higher voltages in a panel of such crystals.
Single crystal silicon wafers are the most efficient means of producing the photovoltaic (PV) reaction, but unfortunately, also the most expensive. There are now other technologies which make the cost-to-benefits of PV better. Instead of growing single crystalline "boules" (long loaf-like single silicon crystals, pulled painstakingly from a molten ingot), it is now possible to "sputter" silicon on to a pane of glass, attach the microwires, and get power in this fashion. Such a process requires a lot less silicon and is less exacting than the old process, and therefore less expensive. Itís also less efficient, and requires more surface area to produce the same power. Silicon is also now "grown" in strips, like sheet steel. This also has driven the cost down.
Nevada has lots of sunlight most of the year. Solar cells work better when they are cool, so you might even find yourself producing more power in the winter! For more information, call below.
- Written by Roger DeNault, SolarQuest, (800) SOL-QUEST
Most of the homes on the tour incorporate photovoltaics. The Swain Home is the largest. The Reslock Home and Animal Ark incorporate a passive sun tracking system in their systems, for added efficiency. The Solomon home has an older system, more integrated into the total "mix" than any of the other homes.
Many of the homes you will see on this tour incorporate the idea of "thermal mass" in their design. What is it? When the sunís rays enter a room, they penetrate and are stored in thermal mass. This mass is usually in the form of an extra mass in the body of the floor, or in a south-facing wall just inside south facing windows. This later arrangement is called a "Trombe" wall. Radiant energy stored in this manner is available to balance any drop in room temperature, such as evening hours or gray days. Some people even deliberately add more mass by adding 55 gallon drums of water and/ or plastic columns of water. Such spaces often become atriums or interior greenhouses.
A similar effect can be produced in a homeís north walls by the use of clerestory windows. Thermal mass is but one element of proper planning in a passive solar home. Also, consider the orientation of windows. During the summer months, when the sun rises in the northeast, crosses directly overhead, and sets in the northwest, passive solar homes are protected from the heat by the absence of windows facing in those directions and by heavy wall insulation. When using thermal mass as a strategy, these homes are also protected by walls so thick and dense that by the time the sunís rays have penetrated nine inches into them, it is night time and the heat exits into the evening air.
- Adapted from the New Mexico Home solar source Book.
Thermal mass is the main component of straw bale houses, like the Glenhill and Larson homes. Check out the Solomon Home and Sierra Nevada College in Incline Village for an approach that integrates thermal mass, hot water collection and PV!
American Solar Energy Society (ASES)
2400 Central Avenue G-1
Boulder, CO 80301 phone: (303) 443-3130
fax: (303) 443-3212, email: firstname.lastname@example.org
web site: http://www.ases.org
ASES is the national, non-profit membership organization dedicated to advancing the use of solar energy for the environmental, economic and social benefits to US citizens and the global environment. Sunrise Renewable Resources Group, an ASES chapter, originally formed in Northern Nevada, has now grown to include Southern Nevada as well. Founded in 1954, ASES promotes the use of all solar energy technologies, including active and passive applications and photovoltaic, wind, solar thermal, and biomass technologies. ASES is the US section of the International Solar Energy Society (ISES).
ASES publishes SOLAR TODAY magazine and sponsors an annual national conference, organizes a national legislative action network, organizes the National Tour of Solar Homes (of which this tour is a part), and has regional, state and university chapters throughout the country. If you wish to join ASES and Sunrise, there are applications on the back cover of this booklet.
Y2K or "Year 2000"
Y2K refers to a flaw in the way software programs were originally written years ago. The concern over this issue, and how this problem may disrupt our conventional energy transmission, is leading many people to seek independence from conventional power sources. Many computers and "embedded chips," controlling transportation, communication and industrial processes will not function properly as we turn the page into the new century. There are billions of dollars being spent worldwide to fix this "glitch Because of potential disruptions to our power and heating systems (Y2K will take place in the winter!), and because of the general feeling for wanting to take more responsibility for their individual environment, many are now considering alternatives.
Y2K is both an problem and an opportunity. The concern generated for this phenomenon will fuel interest in many of the alternative technologies which were just beginning in the 70s. Time and money will be applied to sustainable technologies. A meaningful dialog has already begun. You are part of that dialog by attending this tour!
The Internet is probably your best source of information. Contact me for web site information and more on Y2K:
Roger DeNault, SolarQuest or 1-800-SOLQUEST