I don’t like wearing shoes or socks, but I live in Minnesota so most months out of the year I don’t have a choice. I remember one time when I was a teenager, I decided to walk barefoot down the paved road in front of my parents’ house. It was a beautiful summer day, but my feet later screamed “WHAT WHERE YOU THINKING?!” Yes, the hot pavement scorched the bottoms of my feet. Luckily, a Dutch company has thought of a smarter way to put that hot energy to use.
Ooms Avenhorn Holding BV is siphoning the heat from blacktop roads and parking lots to warm homes and offices. This technology was first dreamed up about 10 years ago, but advances in cleantech and global warming concerns have caused some people to take a second glance.
The technology is called the “Road Energy System” and it’s actually a spin-off of a method to heat roads and reduce the need for maintenance due to cold weather. A grid of flexible, plastic pipes filled with water lay under the pavement and are heated by the sun. As the water is heated, it’s pumped underground, where it stays about 68 degrees Fahrenheit. The water can then be brought up later to heat the road and keep the ice off.
In the Dutch city of Avenhorn where this technology was being used, the engineers found that they were storing more heat than what was actually needed. The solution? Heat the water up a bit more and send it to the floorboards of nearby buildings for warmth in the wintertime. Or, pump the 68 degree water as is to cool the buildings on hot days.
Using this method, a 70-unit apartment building is heated partly by the sun’s energy collected from a 200-yard stretch of road and a small parking lot. Additionally a 160,000 square-foot industrial park nearby is kept warm with heat from 36,000 square feet of pavement.
The system doubles the cost of construction and does need some extra energy for the heat pump that to further warm up the water in the winter. However, commercial manager Lex Van Zaane says this still translates into a 50 percent cut in carbon emissions and a lower monthly heating bill for the buildings.