National Grid electricity system operator (ESO) has reassured the public that it has plenty of power to keep the lights on during the coronavirus lockdown.
The challenge Grid faces is actually the opposite: too much power, too little demand as factories and offices furlough staff and mothball.
As a result, this summer will almost certainly see the lowest draw on the transmission system in modern times, potentially up to 20 per cent lower than last year.
That makes Grid’s balancing act a little more interesting, because a high renewables-low demand system can exacerbate frequency events – where minor wobbles can quickly escalate if not addressed.
The ESO is already looking at how to increase footroom and bring in new flexibility providers – people that can take power off the system, and provide negative responses – in order to keep the power system stable.
It is looking to dust off its Demand Turn Up service, though may have to work around new EU procurement rules in order to start paying people to use power or reduce generation (more on this via our sister site, New Power).
The ESO has also started asking suppliers and TPIs for information on different customer segments in order to better model demand over summer.
In its Summer Outlook, published today, the ESO states: “Managing reactive power, voltage levels, low transmission demand and high volumes of low inertia generation will continue to be challenging.”
As such, it may have to buy more frequency response and reserve products, while paying to keep more responsive plant (such as gas) on the system, curtailing renewables and constraining off less flexible plant. It may also ask pumped storage providers to pump water back uphill when demand is lowest.
Grid also flagged its new sources of inertia, some £328m in contracts awarded to five firms earlier this year as potential problem solvers. However, the majority of those contracts do not start until summer 2021, though the Cruachan pumped-storage hydroelectric power station, now owned by Drax, is due to commence service delivery from June 2020, with Triton Power’s Deeside plant set to follow from August.
To keep voltage levels stable in different regions, ESO mooted setting up contracts that “ensure minimum profitability” to keep generators online, and it may also use the Balancing Mechanism to buy reactive power.
“Should demand levels fall close to the level of inflexible generation on the system, we may also need to issue a local or national Negative Reserve Active Power Margin (NRAPM),” per the report. The ESO said it has done this a few times locally, but never nationally.
See the Summer Outlook here.