Tuesday, November 13, 2012

Solar Greenhouse Uses Underground Heat Sink

As food security becomes an issue everywhere, more and more people are opting for the ability to raise their own food year-round. In the Appalachian Mountains, in Blacksburg, Virginia, the local YMCA has built a solution for climates with cold winters.The YMCA Solar Greenhouse in Blacksburg, Virginia, USA, uses a novel way to store energy collected from the sun: a subterranean heat sink of soil, rocks and water beneath its interior planting beds. This system is called the Subterranean Heating and Cooling System (SHCS), and it collects solar energy and stores it for use when the sun is not shining. This 18'x32' solar greenhouse is constructed with its long axis running east and west, instead of north/south; it employs a heavily insulated north roof as opposed to a transparent or translucent roof on the north side. When outside conditions are very cold, heat is stored during the day in the ground and walls of the greenhouse and released during the night to keep the greenhouse air warm. Other solar greenhouses typically store the sun’s energy in water barrels and/or rocks along the north wall inside the greenhouse - taking up valuable floor space. Conventional greenhouses are also constructed on a long north/south axis, with glazing on both slopes of the roof; conventional greenhouses tend to overheat when the sun is shining and get too cold during winter nights. This solar greenhouse was designed by retired physics professor, Dave Roper. At an estimated cost of $35,000USD in 2010, the greenhouse project could seem out of reach to the average homeowner, but Roper says the design can be adapted to smaller spaces and could be built using recycled materials, which could bring costs down.

Monday, August 6, 2012

Ancient Village Endures 5,000 Years in Scotland

Skara Brae on Solaripedia
Skara Brae was inhabited before the Egyptian pyramids were built, and flourished for centuries before construction began at Stonehenge. After 5,000 years, the houses at Skara Brae still tell a story of the inhabitants' 600 years of culture and history through intact ruins on the west coast of Mainland, Orkney, Scotland. The secret of their endurance lies partly in their semi-subterranean stone construction, as well as being covered by sand for eons. The ten homes were buried in ancient middens - which would have provided effective insulative value - and the buildings are connected to each other via mostly underground passageways, forming a tight-knit little village. In 3,000 BCE, the community would have been farther inland, before the sea eroded the shore to where it is today. There may be a lesson in such stone construction; even Thomas Jefferson counseled against structures made of wood, which he believed could never improve a country to any considerable degree. Wood, he wrote, whose duration is estimated at 50 years, becomes a tabula rasa every half century. "Whereas when buildings are of durable materials, every new edifice is an actual and permanent acquisition to the state, adding to its value as well as to its ornament.”

Saturday, August 4, 2012

Alcatraz Island Completes Photovoltaic System

Two years ago, in June 2010, we reported that Alcatraz Island was planning to go solar.We're happy to report now that the former prison is host to 1,300 solar panels, powering lights and appliances that for 75 years were powered by diesel fuel ferried across San Francisco Bay. Hurray for the National Park Service (NPS) and the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) to bring clean energy to national parks and landmarks! The 307-kilowatt photovoltaic (PV) array sits on the roof of the main Cellhouse building (shown in the photo), attached to two 2,000-amp-hour battery strings and an inverter plant. The new 1,300-panel system produces close to 400,000 kilowatt-hours of electricity a year, reducing carbon dioxide (CO2) emissions by about 337,000 kilograms a year and reducing the time the diesel generator runs from 100% to 40%. The NPS also made energy efficiency changes, such as better light bulbs and changes in operation to reduce energy consumption. A massive solar battery system helps power the island when the sun doesn't shine — and it, too, is hidden from the view of the 1.4 million visitors the island and prison get each year. http://www.solaripedia.com/13/255/alcatraz_going_solar_with_1,360_panels.html

Sunday, July 29, 2012

Can We Learn from Animal Constructions?


Do other animals have anything to teach humans  about sustainable design and building?
The Finnish architect Juhani Pallasmaa points out that animals have developed many inventions familiar to us from our own construction such as roadways (ants), covered streets (termites), deep wells (termites), heating and moisture regulation systems (termites, bees, ants and others), stairways and ramps (termites), and hinged doors with handles (trap-door spiders). He says that human behavior and construction are dangerously detached from their ecological context, partly because we also seek to represent our world symbolically in our construction. Human architecture is always more dictated by cultural, metaphysical and aesthetic aims than by pure functionality and reason, he adds. Other animals, however, fulfill strict criteria for economy and efficiency through minimizing the use of material and labor - sustainable building by necessity for survival and procreation of the species. So how do we combine our technological advances with ecological requirements? Perhaps a look at a few animal constructions can reveal some important answers.

Tuesday, July 24, 2012

Recreation Center in Germany Powers with Solar

On Germany's Bath Island, the Steinhude Sea Recreation Facility supplies all of its power needs. Energy self-sufficiency is achieved with photovoltaic panels, solar hot water collectors, a seed-oil-fueled cogeneration microturbine, daylighting, natural ventilation, passive solar design, building automation, and high-performance materials. These systems provide complete lighting and power needs for the building, as well as enough energy to recharge a fleet of eight photovoltaic-powered rental boats, with excess electricity to sell back to the utility grid. This recreation center also employs graywater reuse and rainwater harvest systems that supply public and staff toilets. http://www.solaripedia.com/13/319/Steinhude+Rents+Solar-Powered+Boats.html

LEED versus Passive House Standards Commentary

Check out the commentary by Jacob Gordon. He reviews LEED versus Passive House standards on The Good 100 blog. Titled "Follow or Get out of the Way: The household name in green construction needs to innovate in order to keep up with the competition." Imagine if teachers gave out grades on the first day of school based on students’ promises of how hard they each plan to study. Oddly, we use this backward system to grade green buildings in the United States.

Friday, July 20, 2012

Is climate change, and a new demographics, creating a "metro moment," or leading to 'It's a a sprawl world, after all"?

by Francesca Lyman, Special to Sacramento Bee - Is our culture inextricably bound up with the boundless American dream of suburbia? Judging from the glossy real estate brochures still selling spacious villas and oversize homes, it seems as though success, for many, remains the fantasy of driving down a wide, palm-tree-lined boulevard among the big lawns and mansions of Beverly Hills, just like the character in Woody Allen's famous scene in "Annie Hall." This latest burst of the housing bubble, however, has exposed the dark underside of the suburban dream – with its cascading foreclosures, shuttered malls and shopping centers – on an enormous scale. 

Many experts believe that coming concerns over climate change, and new demographic and economic trends, will cause a booming demand for infill housing. Others fear there isn't enough supply to deliver on this demand, because infill in cities is so much more expensive. The result could be that we're likely to see the opposite happening -- a migration to sprawling greenfields again.

That creates opportunities for designers and city planners to produce shining examples that make "walkable" work, since real estate watchers do agree on a demand for suburbs to remake their cores in the form of traditional cities and downtowns, says David Mogavero, a Sacramento architect specializing in infill projects. Plus, if the patterns of past development were continued at the same rate, the impact on traffic, air quality and farmland "would be devastating," say urban planners like the Sacramento Area Council of Government's Mike McKeever.

Francesca Lyman, special to The Sacramento Bee, California Forum section
Source:  06/24/2012