Green Energy Features
Energy Efficiency
Altair's unique approach relies on three principles: energy conservation, energy efficiency, and the use of renewable energy sources. The result is a building and energy system which allows us to include heating and cooling in the purchase price.
Energy Conservation: Super-Insulated Construction
Altair's homes require far less energy to heat and cool than conventional buildings. Our construction methods produce buildings whose walls, ceilings and floors are much better insulated, and leak far less air, than other homes today.
One model for this approach comes from Europe, where energy costs have historically been much higher than in the U.S. The ultra-low energy Passive House design, which originated in Germany in the early 1990s, is an airtight, super-insulated home which is built so efficiently that it requires no furnace. All its heating needs are met by passive solar and waste heat from lighting and major appliances, with small electric space heaters as backup for extremely cold days. More than 6,000 passive house homes have now been built in Europe, and they typically cut energy requirements for heating and cooling by 75% to 95%.
While Altair does not intend to eliminate heating and cooling systems, Passive Houses demonstrate the reduction in energy use that can be achieved by building well. Altair has several different approaches that it can use as needed to achieve this. One approach involves a combination of Bio-Based (soy) spray foam insulation and exterior insulation. Another option is Structural Insulated Panels, or SIPS, which are panels of polystyrene or polyurethane foam, sandwiched between two layers of wood or fiber-cement. SIPS can practically eliminate both air leaks and thermal bridging – the heat loss through the wood framing touching the outside wall – which are the two largest sources of heat loss in houses.
In addition, Altair will make use of modular construction, where the components of the building are built off-site in a factory, wrapped for shipping, and trucked to the building site. Modular construction eliminates the possibility of kiln-dried lumber warping from being exposed to outside moisture, which can create a poor fit and cause air leaks. Because construction takes place in a controlled indoor environment, modular also offers significant advantages in speed and construction costs, and minimizes the traffic and noise impact on neighbors. Construction can take place at the same time as site development and foundation work, further reducing overall project time.
Energy Conservation: Geoexchange (Geothermal heat pumps)
Although Altair's buildings will be highly efficient, they will still require some heating and cooling. To deliver that, Altair uses what the U.S. EPA calls "most energy-efficient, environmentally clean, and cost-effective" means of heating and cooling: geoexchange. Also known as geothermal, or ground source, heat pumps, geoexchange uses the energy of the earth to heat and cool buildings. It has been used in the United States since the Second World War, and today an estimated one million homes and other buildings in the U.S. rely on it. The technology does not require volcanic activity or steam vents, instead circulating water and an environmentally-friendly anti-freeze fluid through pipes in the ground, which stays roughly the same temperature throughout the year (50 – 55 degrees in the Philadelphia region).
The drawback for single-family homes has been the cost of drilling the wells for the ground loop, which often go down hundreds of feet, making the initial cost higher than for other heating and cooling methods. For many larger buildings, however, the installation cost is no higher than buying commercial-scale chillers and boilers. By delivering heating, cooling and hot water to the building as a whole, therefore, we expect to achieve efficiencies of scale that will lower the cost.
Renewable Energy: Solar Photovoltaic
The geoexchange system requires electricity to move heat between the earth and the building. That electricity will come primarily from photovoltaic (PV) solar panels on the building roof. While the costs of producing electricity from sunlight is still higher than other methods, costs are falling steadily, and both federal and new Pennsylvania incentives are now available.
If the PV arrays on the roofs of Kimberton Village/Altair generate more electricity than is needed to run the heating and cooling system, the surplus will be sold to the grid.
Smart Home Technology
Giving people digital tools to monitor and control their home energy use can cut energy loads by 15%, according to research published this year by the Department of Energy's Pacific Northwest National Laboratory. Implemented nationally, this technology has the potential to save $70 billion on spending on new power plants and infrastructure. Altair is reviewing existing home automation technology which would allow our homebuyers take charge of their energy use, and make their home more comfortable, for example, by turning off all the lights in the house and adjusting the thermostat to its nighttime setting, with the touch of one button.
Natural Daylighting / Energy-efficient windows
Studies show that allowing daylight into a building improves both the mood and performance of people living or work there. One study showed that students with the most daylighting in their classrooms progressed 20% faster on math tests and 26% faster on reading tests in one year. Businesses have found that adding natural light boosts sales: In 1993, to save money, Wal-Mart put skylights in only half a new store, and discovered that sales per square foot were significantly higher in that half of the store. Altair's homes are designed to maximize natural daylight. Besides being healthier for our homeowners, this will reduce the amount of lights needed during daylight hours, lowering electricity costs.
Low Impact Development
A major area of green development, LID is an extension of an older practice called "permaculture," and plays a vital role in the overall planning of an energy-efficient project. By following the basic rules of LID, developers can produce a project that exemplifies good practice, as well as being in keeping with the planning and engineering of forward-thinking townships.
1) What is LID?
• Long-range approach to land use
• Preserves open space
• Minimizes disturbance of the land
• Protects natural resources on the site
• Works with the natural features
• Minimizes impervious surfaces and run-off
• Decentralizes and manages water
2) Why go with LID?
• It is “doing the right thing,” therefore educational
• Save development costs
• Reduce infrastructure impact
• Lower liability (such as kids disappearing into flared end sections, etc)
• Reduce maintenance
• Increase value and marketability
• Build social capital
• Move the concept, increase its use, regional thinking
• Premium for restored or constructive wetlands, demerits for traditional storm water management
3) How to do LID
• Demonstrate it on a “problem” site
• Develop Smart Growth
• Cluster and vertically zone (thus reducing footprint and impervious)
• Incorporate natural site elements
• Treat water as a resource, not a problem
4) Tools
• Bio-retention and infiltration (the motto is “slow, clean, percolate”)
• Rain gardens, grass swales, ponds
• Green roofs – filtering and storage
• Permeable paving
• Cisterns and rain barrels (this is an international movement, featuring art contests!)
• Continuous process – go from the site selection, overall criteria and goals, all the way to maintenance
LEED Certification
LEED – Leadership in Energy and Environmental Design – is not a technology in itself, but a process for minimizing the environmental impact of buildings, developed by the U.S. Green Building Council. LEED, which is rapidly becoming the nationally accepted benchmark for high performance green buildings, promotes a whole-building approach to sustainability by recognizing performance in the areas of sustainable site development, water savings, energy efficiency, materials selection, and indoor environmental quality.
