Demand response
Demand response was pioneered over 12 years ago , but is becoming increasingly more important .
When a power station ( or one of the cross-channel interconnectors ) fails , the frequency of the mains supply falls very quickly . This happens around 10 times each year . When it does , Flexitricity ’ s critical customer sites immediately take their demand off the mains , and stay off for 30 minutes .
That adds up to around five annual hours of service delivery . But as these are some of National Grid ’ s toughest hours in the year , and as these sites are among the first to step in , the service is well paid .
Setting up a data centre to deliver frequency response is normally low cost , because most of the necessary capabilities are already there . It ’ s often the case that a national frequency disturbance would be picked up by the site ’ s DRUPS anyway , so they have minimal additional capital costs , and frequency response delivery , in its various forms , tends to happen when there is a high chance that the site may be about to switch onto DRUPS power anyway . This means they can participate with little or no impact on day to day operations .
As well as receiving income for participating , there are a number of other benefits . The cost of keeping Britain ’ s lights on whilst new forms of generation are developed represents a significant burden for industry . Reforms to the energy market mean that business electricity users could face a hike in bills in the coming years of around £ 75 per MWh during working day winter peaks – roughly doubling the electricity price during these periods . This represents an average of £ 20,000 per megawatt of average consumption .
So , by turning down energy consumption for short periods when networks are at their most stressed , businesses reduce their exposure to these charges . In addition , all emergency generators – including DRUPS – need occasional on-load running in order to provide reliable emergency power . That works well with demand response – the trick is to ensure that testing is done when the electricity is most needed .
Demand response in context
Demand response is by no means new ; we pioneered it over 12 years to the health of critical generators in particular .
Where data centres stand out
Critical power supplies at data centres have one crucial advantage over other sources of customer-side flexibility – speed . For example , a diesel rotary UPS ( DRUPS ) can act within a second of a failure at a major power station , just as it will when there ’ s a local power cut . However , data centre owners do not want to carry National Grid through all of the minor issues that occur every day . This places their capability firmly in one category : frequency response .
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