Q&A: Schneider Electric says economisers for cooling, air containments and DCIM energy efficiency software top the best green practices for data centres.
A green data centre is defined as a data centre running at very high efficiency or low power usage effectiveness (PUE).
Steve Carlini Sr, director data centre solutions marketing at Schneider Electric, told CBR that these sort of hubs use renewable sources as primary or as secondary power source. These sources could come from hydro energy, geothermal, solar and/or wind.
CBR sat down with Carlini to discuss green data centres from the south rack to the north rack.
CBR: What are the best green technologies/practices for data centres?
SC: There are economisers for cooling, air containments, DCIM energy efficiency software. Note that turning up the temperature in your data centre could actually use more energy.
With larger cloud data centres or data centres with application portability, there is a practice of "following the moon". This is where workloads are either delayed to night-time, when energy costs less, or moved to a data centre on the other side of the world sometimes to optimise energy costs.
CBR: What are the main problems when using green tech, such as renewables, that providers need to consider?
SC: There are issues with renewables production. Hydro may be the most reliable but there are drought conditions that could affect electricity delivery. For wind turbines there must be a wind speed of at least nine mph for them to turn, and for solar there are the cloudy days.
That is why you will find that most of most of these sources are coupled with energy storage on-site to supplement them. With large solar fields, energy isolation must also be built-in to protect the data center from hazardous lightning strikes.
CBR: Why are data centres turning to renewable energy?
SC: Data centres have come under fire recently for monopolising power and water resources at their locations. The demands driven by digitization, big data and the IoT have triggered additional data centre capacity to quickly come on-line.
Data centre planners are spending more and more time planning the optimal location for their data centres, whether it be close to hydro like the Google data centre in Oregon that sources power from The Dalles Dam, or The Green Mountain Data Centre in Norway.
When Green Mountain decided to implement the idea of a green data centre, they needed contractors and suppliers that had the most energy efficient and reliable solutions available in the market. Schneider Electric managed and delivered every data centre infrastructure aspect of the project. This included designing a cooling system that uses gravity to bring cold water from the adjacent fjord to the data centres cooling station, deep within the mountain, a former NATO facility.
This was delivered without using any power or relying on refrigerant gases. Powered by 100% renewable hydro power, Green Mountain supports the critical uptime needs of its customers, operating as one of the greenest data centres in the world – part of their plan to deliver a large ‘zero-emission’ facility.
Google’s Oregon data centre
CBR: Are micro grids the green energy solution for modular data centres?
SC: The concept of micro grids is interesting when discussing more distributed data centres. Essentially a micro grid is a miniature utility. With an intelligent microgrid, you can get tremendous work out of each unit of energy, which results in real cost savings.
To achieve this, you have to reduce loss. Microgrids use distributed energy resources (DERs) that act like small power plants near the buildings they supply, not miles away like large, centralized power plants. So microgrids experience less ‘line loss’ – the disappearance of electricity as it moves long distances over power lines.
In addition, you can reuse heat. Many microgrids use a technology called combined heat and power (CHP), where heat created during power production is reused to create steam and hot water for buildings, industrial processes, or even for cooling. Whereas, conventional power plants waste the heat by-product by letting it dissipate into the air, CHP derives twice the energy from one fuel source, a clear economic advantage.
You can also optimise resources. Because they are intelligent, microgrids can optimise when and how they use central grid and local distributed energy resources. So if it is a hot day and prices peak on the central grid, the microgrid can choose to use its own, less expensive distributed energy resources.
Conversely, the microgrid can buy from the central grid if power prices fall below the cost of local generation. The microgrid also can switch between its different local generation sources as cost and availability of fuel changes. So if electric prices spike during certain hours, the microgrid may choose to rely more on its renewable generation.
Microgrids provide a more cost effective and highly efficient way to incorporate sustainable energy resources into your operation. Use of renewable energy resources such as solar photovoltaic’s and wind turbines are optimized by intelligent software and controls that forecast their expected contribution to the microgrid while also allowing for real-time variations such as passing cloud cover or changing wind speeds. This capability means that renewables are used how and when it makes financial sense.
CBR: What is the biggest emerging trend you see appearing in the green data centre space today?
SE: I do not know if it is quite emerging yet, but there are a couple of floating or submersible data centres in testing.
By floating I mean a system that includes a floating platform-mounted computer data centre comprising a plurality of computing units, a sea-based electrical generator in electrical connection with the plurality of computing units, and one or more sea-water cooling units for providing cooling to the plurality of computing units.
As for a submersible solution, this is an underwater location that could provide the vast amounts of energy needed to run a data center through use of a tidal or turbine energy system, in addition to removing the security risks that come with an easily accessible land location.