Each week, Justin Thomas of Metaefficient gives us a peek into new finds in sustainable design. Metaefficient "searches out products that we believe are more effective and healthier for individuals and the world, yet are comparable in price to mainstream products." We're glad to feature the best of what Justin's found lately, here on Worldchanging:
If you own property that has access to a stream or river, and want to produce your own electricity, then Hydropower should be your first choice. The cost of equipment is lower, and the kilowatt per dollar return is much better than any other alternative energy source.
The most important element to have when producing hydropower is what is called "drop". The greater amount of change in a stream's elevation, the better it is for producing electricity. A small stream with a good drop is better than a larger stream with a small change in elevation, because the turbine needed to tap a small stream is smaller, easier to install and less expensive. Hydropower often produces an excess of power, when used as a direct AC system. This excess can then be used to heat your water or warm your house, for example.
A recent post at Alternative Energy Blog pointed out that villagers in Vietnam are using $20 "Pico Hydro" turbines (300W and 500W) to power their homes, because it is cheaper than buying power from the grid. Apparently these turbines are not available in the U.S. — the only web site selling them is in Nepal.
More details on setting up hydropower systems can be found in this NREL document (PDF).
Composting toilets can be a practical solution even for large businesses. We recently visited the Philip Merrill Environment Center, which is the headquarters for the Chesapeake Bay Foundation. It has a Platinum rating for Leadership in Energy and Environmental Design (LEED) from the U.S. Green Building Council.
After taking a tour of their offices (about a hundred people work there), we tried out their bathrooms, which looked like typical office facilities. The toilets however, are composting ones, so there is no water involved. If you look down the toilet, you see nothing but a pipe leading down into darkness. Designed by Clivus, the toilets emitted no odors — this was probably due to slight draft which was pulling air down into the pipe that lead to the compositing chamber twenty feet below. All odor was drawn away by this ventilation. .
Composting toilet systems which connect multiple bathroom areas into a single composting tank are also available. For example, the Phoenix Composting System can handle daily usage by up to eight people in a household or business. The tanks are insulated, and have an efficient ventilation system with automatic controls over the downward movement of the composting pile. EcoTech USA offers a "Carousel Composting Toilet System" which features four rotatable compost chambers.
The compost container consists of an outer and an inner rotatable container. Excrement, paper and, if desired, organic kitchen wastes are disposed of into one chamber at a time. Liquid drains into the bottom of the outer container, where warmed air drawn into the container evaporates it. The resulting vacuum assures that no odor escapes into the room. When one chamber is full, the next one is turned into position, assuring that fresh waste does not disrupt the more advanced composting material. Another option is to build your own composting toilet; more information about this can be found at the EcoWaters web site.
If there is no water would all toilets have to be directly over the composter? Otherwise wouldn't waste stick to and dry onto the pipe? Would the pipes need to be "chimney swept"?
Yes, composting toilet must be mounted directly above the composter. You can however, have the toilets on different floors of your house.
Gravity micro-flush toilets provide an alternative for installations requiring a toilet not directly above the composter. There's more information on Phoenix web site.