District heating is a system in which a central plant generates heat which is then piped through underground pipes to buildings and businesses throughout a downtown area.
As reported by The Economist, the area is a former industrial zone with low-slung buildings that has been the home to Amazon’s headquarters since 2010 and also boasts a 60-acre tract being developed by Microsoft co-founder Paul Allen.
The system that would be created in Seattle would use heat generated by the massive data centers that power high tech industries.
District heating was once prevalent in many American cities but fell out of favor in the 1970s as utilities found them costly to maintain.
Centralized power plants that use coal, gas or nuclear energy convert one-third of the energy into electricity and the rest is wasted as heat. A combined district utility can convert 40 percent of energy into electricity, 40 percent to heat buildings, lose about 7 percent during distribution, and waste the rest.
In Seattle, buildings hooked up to the system would benefit with the only change being the source of heat generation.
The city is in talks with Seattle Steam, a utility company called Corix and developers in the South Lake Union neighbourhood to build a district-energy system that could harness the wasted heat from two nearby data centres (Westin Building and Fischer Plaza), reports The Economist. It could heat new buildings, including, potentially, the towers that Amazon has just begun erecting that will add 3m square feet (280,000 square metres) of office space.
Currently, excess heat from the data centers is collected in water and funneled to cooling towers. This water is not enough to heat buildings, but Corix could divert it to a new Seattle Steam facility to be heated further. From there it would be piped to buildings and circulated through radiators.
Some uncertainties exist, like how much the data centers would charge for the hot water. Project developers have not yet committed to the concept, either. Also, conversion of existing systems from electric heat to radiators would be expensive, or perhaps building features like thin walls may not be conducive to the installation of hot water pipes.
Construction permits and the need to share underground space with existing infrastructure like electric and telecommunications lines could also be problematic.
Short-term costs could, then, ultimately derail the project, as they did in the 1970s. Seattle has commissioned a feasibility study but it too has yet to make a firm commitment.
Heat from data centers has already been used as a resource elsewhere. Canadian telecommunications company Telus is building a $750-million residential and commercial complex in downtown Vancouver, BC, and is going to heat and cool the new Telus Garden development with waste heat from its own nearby data center.
A renovated hotel, near Seattle’s International District, has completed installation of a hybrid solar-thermal system that will supply heat and hot water to the building’s 254 apartments and studios, as well as to new retail storefronts.
Photo credit: Transit Nerd’s Flickr photostream