Solar Hot Water System 1.
ENVIRONMENTAL BENEFITS Electric and gas hot water systems typically account for approximately 20% of a household’s greenhouse gas emissions. By installing a solar water system, energy use is reduced by about 75% as compared to traditional systems. In this off-the-grid house, use of a solar hot water system significantly added to the viability of energy self-sufficiency. The evacuated tube system employed at this house consists of a glass tube with a vacuum inside and copper pipes that are all connected to a common manifold. This is then connected to a slow flow circulation pump that pumps water to a storage tank below, thus heating the hot water during the day. Insulation in the tank keeps the water hot for use at night and the following day. The evacuation tube systems are superior to other systems as they extract the heat out of the air on a humid day, not requiring direct sunlight. Due to the vacuum inside the glass tube, the total efficiency in all areas is higher and there is better performance when the sun is not at an optimum angle - such as early in the morning or in the late afternoon. As heat rises, the hot water delivered to the tank from the solar collector is drawn from the top for use in the house. When the temperature of the water exceeds 60 degrees Celsius, as is required to kill bacteria, a tempering valve reduces the temperature to about 45 degrees Celsius, in order to ensure a safe temperature at the taps. While the sun provides the house with sufficient energy and plenty of hot water for most of the year, extended periods of cloudy weather sometimes require a boost, provided by an auxilary gas booster system. Using a tankless gas water heater is the most efficient method, as boosting only occurs when hot water is used. With an electric system, the tank is heated as soon as the internal temperature drops, requiring excess energy use.
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SUB-CONTRACTOR Jason Borner Poderco, S.A. APDO 61 Puerto Jimenez de Gulfito Costa Rica, A.C. 011-50-62-735-5843
Casa Torcida
Osa Peninsula, Costa Rica
[ SPG ] architects
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