National Grid says impact of solar requires greater system flexibility


solarNational Grid has predicted all-time lows for power demand on the transmission system this summer due to the boom in distribution-connected solar PV.

The system operator also warned that it may have to issue emergency instructions to inflexible generators over the summer, whom it will pay to stop exporting power onto the system. It may also need to call on new demand-side response tools that ask firms to increase power use.

Sunny outlook

According to Grid’s Summer Outlook, published today, the peak demand forecast for high summer, at 35.7GW, is the lowest on record, some 2GW lower than last year. Daytime minimum demand is expected to be 23.5GW, around 2.5GW lower than the minimum demand experienced in 2015.

Those drops are driven largely by increases in embedded solar PV capacity, which, according to Grid figures, almost doubled from 5.0GW in April 2015 to 9.3GW in February 2016. The system operator has assumed PV will continue to increase, albeit at around half that rate, by 200MW per month over the next year. It predicts total solar PV capacity to reach 12.0GW by the start of BST 2017.

The system operator said forecasts indicated it would have sufficient capacity to meet demand, even with low interconnector imports during July and August, when generators tend to carry out annual maintenance.

Flexible demeanour 

However, Grid said the changing generation mix and demand profile would require more direct system operator intervention and a more flexible approach to system balancing.

It may use demand-side response tools, such as the new demand turn-up scheme, should the system have more power than it can cope with, as well as asking inflexible generators to reduce their output. Current data suggests that will most likely happen during the weeks commencing 20 June, 25 July and 29 August, said Grid.

Read the full report here.

Related stories:

Government backs Adonis’ smartgrid plan, pledges £50m+ for storage and demand response

UK must prioritise smartgrid, says National Infrastructure Commission

Free download: Demand side response report 2015

Decc commits to annual plan and to consult on energy storage

National Grid to tender for 200MW of superfast demand response next month

Major changes to capacity market proposed

Hot technology: energy storage via heat battery

Western Power Distribution ramps up demand-response trials, calls for participants

Smart grids ‘require local control and businesses must play or pay’

National Grid must simplify demand response to scale UK market

40% of firms say they could shift energy use as National Grid asks them to turn up

Dong enters demand-side response market with wind power balancing service

National Grid buys 475MW of demand response to cover winter

2016: the year half hourly settlement will hit your power bill

Government to consult on demand response in spring

Energy Technologies Institute: Let private firms run smartgrid trials

Flexitricity blasts transitional capacity market as Npower plots supermarket sweep

Grid buys 3.6GW of back up power to prevent blackouts

Flexitricity warns demand response cannot be rushed as winter looms

National Infrastructure Commission to focus on energy storage and demand response

Is Triad past its peak?

Tempus: A five year old can see capacity market is anticompetitive

National Grid plots superfast grid balancing service

Many major energy users can’t be flexible, says manufacturing chief

National Grid moots demand side response rule changes as winter power margins tighten

Keep calm and scale demand response, says Scots energy inquiry

National Grid flags demand response changes, urges suppliers and TPIs to deliver

National Grid must simplify demand response to bring in UK businesses

Ofgem boss flags rule changes to speed demand response

National Grid launches major demand side push

Demand response: Suppliers and aggregators ignoring 80% of UK firms

UK firms with CHP plant could be paid to stop exporting power

National Grid: No margin? No sweat

Demand response provider teams with Honeywell, touts for new business

Free report: Directors’ energy outlook report 2016

Free report: How to finance energy efficiency

Click here to see if you qualify for a free subscription to the print edition of The Energyst, or to renew.

Follow us at @EnergystMedia. For regular bulletins, sign up for the free newsletter.


  1. A cheeky advert: anyone looking to use their own PV panels to do something useful rather than just send their power off to the grid could do worse than consider our direct PV-driven cooling systems, made by the world’s largest AC company and available now in the UK.


Please enter your comment!
Please enter your name here