Living up to its green credentials, Dutch plans to use the waste heat and CO2 from a datacentre located in the heart of a greenhouse farm are starting to take shape.
The most important thing we have learned so far is "that it is too easy to simply say you are going to reuse heat from a datacentre for other purposes". So says Kevin Burton, director at Parthenon Data Centres in Holland.
The Dutch company plans to break ground in December 2010 when it opens a facility that uses energy generated by the operation to heat adjacent greenhouses.
"You must have mechanisms and processes in place to account for the low-value nature of the heat and the fact that the datacentre is producing heat 24 hours a day, 365 days a year, and that it is not always needed," says Burton.
"We are using the residual heat from the greenhouses and have to get the temperature up. A byproduct of the heat exchange is that we are left with a lot of chilled water. This means we can use the chilled water to re-cool the datacentre.
"We will run the datacentre on free air 90% of the time, and 10% of the time we are using chilled water; we are getting it for free. We anticipate a power usage effectiveness (PUE) of close to 1," says Burton.
The exchanges make sense, but where does the heat go when it is not required? It goes underground.
Below the site is an aquifer, which feeds a reservoir that will store the heat, losing only 1-1.5°C over a 12-month period, according to Burton. Both hot and chilled water will be stored below ground.
The issue of raising the value of the heat has begun with plans to run the cold aisle inlet temperature at 27°C. Any higher, says Burton, and the server fans will begin to kick in, overcompensate and run faster, using more electrical energy and negating any benefits. "It is all about striking a balance," he says.
"In the Netherlands we have had great assistance from the government. They are very proactive on green energy. We have had some subsidies in relation to energy saving, and we are looking at further subsidies the closer [we get] to the build. It has now been proven technically by leading engineers as well as theoretically," he says.
The project is being seen as an export opportunity by the Dutch and conversations have started with organisations as far afield as New Zealand about the reuse of datacentre heat for industries that are similar in scale and operation to those that are greenhouse-based.
The developer is now looking for an anchor tenant, saying that the project has spurred a great deal of interest among some of the major IT suppliers, including IBM, with which negotiations are ongoing.
This article first appeared in DatacenterDynamics Focus magazine.