After Gutenberg

As previously noted, solar hot water is a good deal that keeps getting better as the cost of other means of hot water heating increases. “An investment in a solar hot-water system could even be considered patriotic,” writes Bob Ramlow, “because solar keeps our energy dollars at home and reduces our dependency on others. You’ll pay to heat water in any case — why not choose to do it with solar energy? Your pocketbook, and the environment, will appreciate it.”

OTOH, AG commentator country mouse noted in regards to solar hot water systems:

These systems are not designed to be repaired. They break by leakage, loss of installation through weather, mechanical, or solar degradation (UV) of various components.

I have yet to see a solar hot water system remain in good shape for more than five or so years. I would love to be proved wrong. I know there are instances that go for 20 or 30 years, but I’ve seen far more of them go dead in five to 10 years than I have seen go longer.

10 years ago Ooms Avenhorn Holding BV came up with their Road Energy System that siphons heat from roads and parking lots to heat offices and homes.

Arthur Max wrote a story distributed by the Associated Press about a somewhat different application of the same principles. The AP story is about way of obtaining energy from roads designed by civil engineering firm, Ooms Avenhorn Holding BV.

Solar energy collected from a 200-yard stretch of road and a small parking lot helps heat a 70-unit four-story apartment building in the northern village of Avenhorn. An industrial park of some 160,000 square feet in the nearby city of Hoorn is kept warm in winter with the help of heat stored during the summer from 36,000 square feet of pavement. The runways of a Dutch air force base in the south supply heat for its hangar.

Storage of thermal energy requires super insulation techniques in addition to a latticework of flexible pipes, held in place by a grid, which is then covered with asphalt, “Ooms’ thermal energy system is actually a spin-off from attempts to reduce road maintenance and costs.” Since the installation cost of such system is more expensive than others and it employs energy-efficient construction for the thermal storage, it begs the question whether it could be more cost effective to improve the building envelope, e.g., insulation, windows, controlled ventilation, and employ the use of energy-efficient appliances and lighting in the buildings selected to receive heat from the solar collectors embedded in the pavement