by Deanna Seay and Debbie Piesen
Living Energy Farm (LEF) is an income sharing community, organic farm, and environmental education center in Louisa, Virginia that uses no fossil fuels or grid electricity. We are currently four adult members and four children. Our mission is to address the issues of climate change and income inequality through example, by demonstrating that a comfortable and fulfilling life is possible- and affordable- using only sustainable, renewable energy. The most important technology we use is community: living cooperatively and sharing resources is what makes renewable energy practical and affordable.
EarthHeart- the main residence at Living Energy Farm. When one walks up the hill,
this building is the first to display one of the many renewable energy technologies
that are used at LEF. In this case, solar hot air panels and solar water heaters are
mounted on the roof. The solar hot air panels heat up air which is blown under the
building in the winter, and the solar water heaters use the strength of the sun to
heat water. Furthermore, the southern exposure of these windows allows the entire
house to absorb the winter sun, and the straw bale insulation prevents the warm air
from escaping. In the summertime, south facing windows do not collect much
sunshine, and east and west facing windows can be covered to reduce the amount of
radiant energy passing through. The strongly insulated building will also help moderate summer temperatures.
How does one source electricity in a zero-fossil fuel environment? Solar panels!
There are two arrays at LEF; the one pictured to the left is the low voltage array and
will power LED lights after dark. These panels will charge a battery- and not just any rechargeable, solar compliant battery. LEF will use Nickel-Iron (NiFe) rechargeable
batteries. Unlike the more common lead-acid batteries, NiFe batteries are non-toxic and do not degrade over time. The one currently being tested at LEF, pictured below, is ninety years old- an original model made by the Thomas A. Edison company in West Orange, NJ!
The second solar array is a high voltage, direct-current system that is used to run
the water pump, fans, and any equipment needing more power. This system (see picture below left) harnesses the sun with customary photovoltaic panels, and produces enough energy to power this saw (below right) used for cutting wood. This system is only used when the sun is shining, eliminating the need for expensive
electronics like inverters and batteries. Instead of storing electricity, we store the
energy in other forms: cut firewood, water in a storage tank, heated thermal mass.
People sometimes ask us why we don’t use solar electricity to cook. The answer is that it is very inefficient to produce extremes of temperature with electricity. It would take a system much more expensive and elaborate than ours to cook with photovoltaics. Solar thermal, using the heat of the sun directly without turning it into electricity, is much more efficient but still limited to when the sun is shining (see below). When we want to cook other times, we rely on firewood.
Living in the rural countryside, wood is abundant, but we still try to minimize our
demand (and emissions) by using super-efficient rocket stoves. The ones we use are made by Stove Tec. The most difficult aspect of the rocket stove can be simply getting it lit…damp days provide a challenge. The rocket stoves at LEF are set up outside under a cover, and one is enclosed in a flue which directs the ash and smoke away from the cooking area. This is the stove used for open pot cooking such as sautéing vegetables. The other stove is used when there is a lid on the pot.
If there is ample time, food can be partially cooked on the rocket stove and then completed under the “hay box,” or hot box. Once upon a time made out of hay, this
contraption is pretty much an insulated box lined with reflective foil. The pot with
hot food is placed into the box and left alone…good for things like rice, quinoa and
anything else that needs to simmer.
Another option, with enough planning and sunshine, is the parabolic cooker- also known as the “death ray.” A pot is hung over the middle of the reflective dish, and the light is focused on the bottom of the pot. Remember watching fires be started by focusing sunlight through a pair of eyeglasses? This system uses reflection to achieve the same result. It is a little tricky at first as the details are very important; the pot should hang at an optimal distance above the dish to allow for a tight “focal point”; the pot should not be too big; the dish needs to be adjusted as the sun moves across the sky. Once these elements come together, however, this solar cooker is very effective.
Finally, we have the solar oven, which is brilliant for anything that needs to be baked. Open the lid, place the food inside, close the lid and aim towards the sun. This oven bakes bread, potatoes, etc as well as a conventional oven would. The only drawback is that the sun needs to be shining…this is not an activity to be saved for a rainy day!