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similar systems modelled after the Stanford experience. Institutions like Dartmouth and Harvard have been over to see the project in California, and we’re talking to them about the possibility of converting their legacy steam networks to EN hot water.” “We have experienced a substantial reduction in operations and maintenance related to heat distribution following conversion from steam to hot water,” says Ron Gawer, Director of Energy Operations at Stanford University. “We have reduced maintenance costs, as there are no steam traps or associated check valves, strainers, and threaded fittings to PM and repair, and no manholes to pump during rainy weather. We have also reduced heat loss in the underground piping, reduced heat loss and the associated cooling load in building mechanical spaces, cooler and less humid mechanical spaces which reduces the corrosion of other mechanical equipment, reduced maintenance in mechanical rooms due to no pressure reducing stations or condensate pumps to maintain, and zero complaints that I know about from buildings about inadequate heating.” Recently, the overall SESI project received an award for 2016 Global Best Green Project from Engineering News-Record, an award Stanford shared with Affiliated Engineers, Inc., the prime consultant and lead engineer. “We as a team got together in New York City at the end of last year for the award,” says Mr. Vreugde. “It’s very gratifying to see the project receive all these accolades.”

LATEST TRENDS As the state-of-the-art moves forward, Mr. Lorenzen expects the new trends which are appearing in pre-insulated hot water piping in Europe to transfer to North America shortly. “There’s a new trend where, instead of two single pipes, we bundle the supply and return together into what we call TwinPipe,” says Mr. Lorenzen. “That allows you to reduce heat losses up to 50%. Today in Denmark, more than 70% of the new pipe that’s being installed is TwinPipe. We’re also now seeing district heating companies trying to reduce the supply temperature. Previously, you sent out heat from district heating production at maybe 90 to100 degrees, and it came back at 60 or 70. What people are trying to do in Europe is to lower that forward temperature to reduce heat losses.

Another exciting development is what we call fourth-generation district heating networks. Those are networks where they’re trying to combine the way the district heating is used with an overall system. So you think about how you’re integrating the district heating with the electricity you’re getting, and when you’re using the heat, and so on. It’s a wider picture, where you consider how to operate a municipality in the best way.” “Globally, we see lots of wasted surplus heat in cities.” says Mr. Lorenzen. “So instead of throwing all that heat up in the air, why not capture it, and distribute to local buildings in the form of hot water? So the big picture is saying: Why don’t we use the surplus heat we have in the world? It’s there anyway; we have it for free. We just have to convert it to hot water.” c




Sustainable Business Magazine 01/17  

Sustainable Business Magazine