Energy Efficient homes are the future
Building the ultimate green home can be expensive. Finding a proper balance between construction cost and energy efficiency is ideal. Even if you have an existing home, making energy efficient upgrades can be costly.
Save Green Home is dedicated to providing all the resources to help you find the ideal balance between energy efficient and cost. You'll find insightful information regarding tankless water heaters, wind turbine and solar panels as well as energy saving ideas throughout the building steps. Also some government tax incentives that can make your project virtually free....
Energy News
3M
2010 news: 3MTM is investing $200 million in new plastic film production as its targets a major business opportunity in solar and other renewable energy technologies.
The company recently completed a manufacturing expansion in Singapore for 3M ScotchshieldTM Film, a leading solar film critical to the manufacturing of crystalline silicon photovoltaic (PV) modules. Dyneon Scotchshield Film 17 utilizes a multilayer construction consisting of an outer fluoropolymer film bonded to a proprietary PET film, which is bonded to EVA film to complete the multilayer backsheet. This inner EVA layer of the backsheet bonds to EVA cell encapsulants during the PV module lamination process.
The 3M multilayer film in the patent includes a polyester intermediate layer and outer layers of semi-crystalline fluoropolymer with a tensile modulus of less than 100,000 psi and an olefinic plastic, such as polypropylene. The layers could be produced through a conventional coextrusion process or via thermal lamination.
One of the key aspects of the new approach is the preshrinking of the polyester layer prior to thermal lamination. "Pre-shrinking of the film after the addition of other layers can become exceedingly difficult especially if one or more of the additional outer layers has a softening or melting point that is within the temperature range required to pre-shrink the intermediate layer," according to the 3M inventors.
The thickness of the individual layers within the multilayer film can be varied based on the requirements. 3M says it expects the outer layer of fluoropolymer will be from about 0.5 to 5 mils, preferably 1 to 2 mils thick; the intermediate layer will be from about 1 to 10 mils, preferably 2 to 4 mils; and the outer polyolefin layer will be from 1 to 20 mils or greater. Preferably it is 10 mils or greater.
Soliant:
A new mechanism for focusing light on small areas of photovoltaic material could make solar power in residential and commercial applications cheaper than electricity from the grid in most markets in the next few years. Initial systems, which can be made at half the cost of conventional solar panels, are set to start shipping later this year, says Brad Hines, CTO and founder of Soliant Energy, a startup based in Pasadena, CA, that has developed the new modules.
Concentrating sunlight with mirrors or lenses on a small area cuts the costs of solar power in part by reducing the amount of expensive photovoltaic material needed. But while concentrated solar photovoltaic systems are attractive for large-scale, ground-based solar farms for utilities, conventional designs are difficult to mount on rooftops, where most residential and commercial customers have space for solar panels. The systems are typically large and heavy, and they're mounted on posts so that they can move to track the sun, which makes them more vulnerable to gusts of wind than ordinary flat solar panels are.
Soliant has designed a solar concentrator that tracks the sun throughout the day but is lighter and not pole-mounted. The system fits in a rectangular frame and is mounted to the roof with the same hardware that's used for conventional flat solar panels. Yet the devices will likely cost half as much as a conventional solar panel, says Hines. A second-generation design, which concentrates light more and uses better photovoltaics, could cost a quarter as much. He says that a more advanced design should be ready by 2010.
SunPower:
When it comes to solar technology, no one is better equipped to separate the genuine potential from the hype than the Department of Energy, which spearheads the country's solar research efforts. So it's worth noting that the DOE's choice for the brand-new 205-kilowatt solar installation on the roof of its Washington, D.C., headquarters, unveiled in September, was the unique high-efficiency solar panels built by Silicon Valley-based SunPower Corporation.
Energy Secretary Samuel Bodman called the choice "both practical and symbolic," and he was right. It's practical because, earlier this year, SunPower's silicon photovoltaic cells demonstrated an efficiency of 23.4 percent—a record for large-scale, mass-produced cells. SunPower uses what's called a "back-contact" design, which means that all the electrical contacts are on the back of a cell, leaving a larger area on the front of the cell exposed to the sun. Such designs have always been efficient, but it's only in the last few years that manufacturing costs have become competitive.
For SunPower, at least, the wait is over. With PV cells that the company boasts as 50 percent more efficient than conventional crystalline silicon cells, SunPower is moving full steam ahead, most recently with an agreement to build a 250-megawatt "solar ranch" in the California Valley. The project should begin delivering power in 2010 and will be—at least temporarily—the largest PV installation in the world.
