Heat Rises - Re-Using the Heat Generated by Servers By Saleh Tousi

With the green movement getting more and more attention every day, data centers are starting to get more and more flack for the amount of power the use up and companies are looking for ways to start "greening up." Most of the initiatives that data facilities are taking involve recycling the power within the facility, using energy-efficient servers and cooling the server room more effectively. These efforts are great and lead to less wasted energy and a more efficient system.

But with all the attention focused on saving, little is being paid to making better use of the existing heat generated by the servers. As it stands, this heat gets wasted. It's removed from the facility by whatever cooling system the data center uses. Most commonly this is in the form of air conditioning or water cooling.

Missed Opportunity

But what if there was another way - what if the heat generated by the servers could be put to better use? There is. The solution lies in using the heat generated by the servers and putting toward something useful, rather than simply discarding it in the atmosphere.

Energy is wasted all the time these days. Companies spend thousands of dollars to remove the heat from their server room, while simultaneously spending more money to heat other parts of the building. This wasted heat is a missed opportunity in energy efficiency.

There are a few companies that have seen this opportunity and have taken the initiative to put the heat generated by servers to good use. There is no limit to the potential that this has when harnessed and used productively.

Heat Recirculation

One example of a company using the existing heat from the servers is Quebecor, a Canadian media company. Located in Winnipeg, where temperatures frequently reach 35 degrees below zero, Celsius in the winter. The company found that even during the coldest months of the year, they were spending thousands of dollars cooling their data center, despite the harshly cold temperatures outside. At the same time, they were spending just as much money heating up other parts of the building.

It just didn't make sense. Fortunately the regional director for the company saw this as an opportunity for the company to reuse the heat generated by the servers which helps save energy all around and at the same time reduces costs. So that's exactly what he did. Instead of merely cooling the server room, he implemented a system whereby the excess heat was harnessed and pumped into other parts of the building to provide heat.

The heat generated from the servers is used to heat the offices upstairs which host the Winnipeg Sun. Additional heat is allocated to the warehouse across the street which is often chilly due to the door opening and closing all day. Whatever heat is left over is put back outside.

Heating a Swimming Pool

Another company in Switzerland had a similar idea of putting heat generated by servers to good use. This company is located about 25-feet underground and 500 feet away from a swimming pool. Instead of wasting the heat generated by the servers, the company decided pump the heat into the nearby swimming pool in order to provide it with the necessary heat. Using custom-made cooling units overhead and powered by 200 servers, they are able to use the hot exhaust air to heat up the water and then filter it into the pool. This creates a practical use for the excess heat while simultaneously eliminating the need for the pool to use oil as its energy source.

Going Green(house)

The latest example of a data center putting their excess heat to good use is at the University of Notre Dame. Raising energy costs are forcing the local greenhouse to shut down. Currently it costs around $1,000 a day to heat the greenhouse, which politicians have decided is too much to ask taxpayers to pay.

That's where Notre Dame comes in. They've developed a new type of data center that's housed in a standard shipping container and placed right next to the greenhouse. The excess heat from the data center will be pumped into the greenhouse to heat it. This will reduce the costs of running the greenhouse enough so that it won't have to shut down.

As an added bonus, the data center will be able to use the humidity generated by the greenhouse in the fall, winter and spring. This reciprocal relationship benefits not only the greenhouse, but the servers as well.

Future of Heat

Reusing heat from data centers has many applications and lots of potential as an energy-saving initiative. Most companies aren't thinking along these lines though. But they should. Creating more efficient servers and cooling systems, reducing the amount of heat generated, and reusing the heat that is generated are all integral components of an energy-efficient data center. Companies have many options to choose from and reusing excess heat is yet another way they can help reduce the amount of waste produced in their facility.