Intelligent Data Centres Issue 41 | Page 45

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Demand Response offers the opportunity to generate new data centre revenue streams while supporting the utility grid and its use of renewables increases .
People whose job title is head of engineering , VP of data centres or general manager of infrastructure in the data centre space are constantly thinking about sustainability . That means seeking appropriate solutions to cut carbon emissions . It is a huge challenge which also creates many opportunities . To realise these opportunities means creating a data centre of the future in business and technology infrastructure terms .
To sustainably power a data centre involves interaction with power generators and power grid operators . The context for such engagements is the national and regional strategies that are seeing huge energy firms transition to net-zero while maintaining energy security .
How will data centres engage with utilities and grid operators as both power consumers and power suppliers , while maintaining power to the load and meeting their own sustainability agendas ? Whether buying or selling , which actions will have the most immediate and most beneficial impact will depend on the data centre ’ s location , size , age and type ( namely hyperscale , colocation or enterprise ). Engaging as a power supplier raises questions about the technologies data centre operators can deploy in order to build sustainable and profitable partnerships with grid operators .
What is Demand Response ?
Demand Response ( DR ) can be described as customers modifying their power generation capacity or consumption requirements with the goal of reflecting supply expectations through consumer price signals or controls . DR is achieved by consumers reducing energy consumed or by returning energy to the grid-based upon either the predicted day-ahead market or the instantaneous real-time market .
The data centre industry is uniquely positioned to participate in DR to reduce its own carbon emissions and generate additional income for data centre owners . many forms of Demand Response
The simplest type of DR participation is Load Curtailment . The data centre disconnects from the grid and runs on its own power generators in island mode . Next is Load Shifting , which would see data centre power consumption reduced during a period of peak grid demand by shifting energy use to another time of lower demand . In some circumstances , for example , it may be viable to reduce load to allow the on-site battery storage to partially discharge and support the IT load in parallel with , or in isolation from the grid .
Another form of DR is Short Term Operating Reserve ( STOR ) and Load Reduction . In this case , the utility requests additional power when demand on the grid is higher than forecast , or in the event of unforeseen generation unavailability . DR providers help to meet the reserve requirement either by providing additional power generation or reducing their own demand .
STOR requires several capabilities on behalf of the data centre operator , including the capacity to supply power to the grid ; the ability to respond to a utility signal usually within 20 minutes ; to sustain that response typically for a minimum of two hours ; to be able to respond again with a recovery period of no more than 20 hours .
Data centre participation in STOR involves supplying the grid and the data centre from its generators , which will therefore require the available data centre generating capacity to be significantly higher than its load . Perhaps the most lucrative DR service which data centres could supply is Frequency Response . This helps utilities counter unplanned power generation and load imbalance that would otherwise cause a frequency stability problem . Three types of response are :
• Fast frequency response ( FFR )
• Frequency containment reserve ( FCR )
• Frequency restoration reserve ( FRR )
More details regarding Frequency Response as well as other types of DR services can be found in a free to access
FEATURE
Whitepaper published by i 3 Solutions Group , Demand Response Opportunities for Data Centre Embedded Generation and Energy Storage Systems . The question of how much under-utilised power capacity exists in the world ’ s data centres is one of some speculation . At a macro scale , it is certainly multiple Gigawatts .
Demand Response – Infrastructure concerns
Data centres were not designed to be bi-directional microgrids but were meant to operate as unidirectional microgrids occasionally , i . e . during a utility failure when generators are used to supply the data centre load . Among the challenges to becoming bi-directional are that not all existing power capacity is readily available nor suitable to power a grid .
Data centre power chains are composed of a mix of technologies , meaning creating suitable bi-directional power flow poses technical and sustainability challenges .
First , if we consider the on-site power generation and storage infrastructure , it is most likely to be diesel generator-based to provide emergency power , with either lead acid or more recently , Lithium-ion batteries to provide energy ride-through .
Diesel generators can run directly on HVO or be converted to run on cellulosic fuels . Usefully , practically all data centres are designed to provide many hours of power during a utility outage and therefore are inherently suited to provide load curtailment when run with
Ed Ansett , Chairman and Founder , i 3 Solutions Group www . intelligentdatacentres . com
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