Your commercial battery can save you money by storing cheaper grid electricity or surplus solar power, then supplying your site when electricity prices are higher. Batteries can also help you stay within your grid connection limits, meaning you avoid penalties and may not need to pay for more capacity.
If your battery has spare power at the right time, taking part in the Demand Flexibility Service could provide an additional source of income. Find out below (x).
What is the Demand Flexibility Service?
The National Energy System Operator (NESO) runs the Demand Flexibility Service (DFS). NESO is the organisation responsible for keeping supply and demand for electricity balanced across Great Britain.
At certain times, NESO calls an “event”. An event is a set period when it asks homes and businesses to use more or less electricity than they normally would. It’s this action that you receive payment for.
How does my business get paid for taking part in the Demand Flexibility Service?
First, you need to join the DFS through a registered provider, like your electricity supplier or an energy aggregator.
When you respond to an event by increasing or reducing your electricity use, NESO pays your provider, which then passes your agreed share on to you, subject to any fees or deductions in your agreement.
How does my provider calculate my Demand Flexibility Service payment?
Your provider compares your “baseline” with your meter readings. In DFS, your baseline is the amount of electricity your site was expected to take from or send to the grid.
How is your baseline worked out? Usually, your provider looks at your meter readings from the same time on similar days. The difference shows how much more or less electricity your business took from or sent to the grid during the event.
Your provider then uses the event price to work out your payment and deducts any fees in your agreement.
Your payment statement should show:
- Your baseline
- What your meter recorded
- How much your electricity use changed
- The price used
- Any fees
- The final payment
Can my commercial battery take part in the Demand Flexibility Service?
You can take part in DFS if your flexibility provider can:
- Control the times at which your battery charges and discharges
- Use your meter readings to show how much electricity your business took from or sent to the grid during the event
A flexibility provider can be:
- Your electricity supplier: If it is registered for DFS, it can sign up your business, submit bids to NESO, and pay you for the response you deliver
- An energy aggregator: Aggregators combine the response available from your battery with that of other businesses and submit it to NESO as a larger bid
- A virtual power plant (VPP) operator: A VPP operator controls batteries and other energy equipment across several sites as one connected group. The operator may submit DFS bids directly or work with a separate registered provider.
To take part in an event, you need enough spare battery power and stored electricity at the time of the event.
When should my commercial battery not take part in a DFS event?
Your flexibility provider should not enter your battery into an event if your business needs the power for something more important.
This may include times when:
- You need the battery to reduce expensive grid use later
- You want to keep stored solar electricity for your own use
- You need to keep some charge for backup power
- The battery does not have enough power or stored electricity to see through the entire event (for example, it could deliver the required response for only 20 minutes when the event lasts 30 minutes)
- Taking part would push the battery below its minimum charge level, above its power limit, or beyond the cycling limits covered by its warranty
- The provider cannot control the battery or confirm the response from your meter readings
How does a flexibility provider decide whether to enter my battery into a DFS event?
It’s the job of your flexibility provider to check every potential use of your battery before it recommends taking part in the event, once it is certain that taking part will not leave your business without the battery power it needs.
If your business still has enough battery power, they then check whether DFS is the best-paying use of what is left.
For example, a DFS event may take place at 4pm, but your business may need the battery to reduce expensive grid use at 5pm. If using the battery for DFS would leave too little charge for the later peak, the provider should not proceed.
At another time, the battery may already be charged, your business may not need it, and no better trading opportunity may be available. In that case, entering the battery into the DFS event could bring in extra income without affecting its other jobs.
The provider should repeat this process before every event because electricity prices, battery charge, and your site’s needs can all change during the day.
What will a flexibility provider need before I sign up for DFS?
A flexibility provider will start by asking for the make and model of your battery and inverter. This will allow them to see if their software can control them on-site and remotely.
If it is compatible, they’ll then ask for further information about your meter, battery size, electricity use, and any power you need to keep for the business.
You do not need to gather all of this before getting in touch.
Use your commercial battery for DFS with GridVolt
GridVolt’s Energy Manager software will connect directly to compatible third-party batteries and inverters. You can keep your existing equipment and electricity supplier if you work with us
Energy Manager checks your site’s electricity use, tariff, solar generation, battery charge, and any power you want to keep in reserve. Every 15 minutes, it decides whether to charge the battery, discharge it so your business takes less electricity from the grid, keep some charge in reserve, or use spare capacity for DFS and other trading opportunities.
For suitable sites in Great Britain, GridTrade can use this spare capacity to take part in the Demand Flexibility Service. Before each event, it checks whether DFS is likely to pay more than another available use of the battery. It only proceeds when your site has enough power left for its own needs.
To find out more, fill in the form on the right or get in touch via the contact page.
Demand Flexibility Service: frequently asked questions
Is the Demand Flexibility Service run year round?
Yes. DFS has been operational year-round since November 2024. Prior to that, it was only available during winter. NESO amended the service again in April 2026. Businesses can now receive payment for using more electricity at certain times as well as using less.
How much does the DFS pay?
There is no fixed DFS payment for taking part in an event. What you do receive depends on the price accepted for the event, how much more or less electricity your business uses, whether your battery delivered the full response, and any fees or revenue share charged by your provider
NESO pays your provider and your provider then works out how much they pass on to you under the contract you’ve agreed to.
How long does a DFS event last?
Your battery must be able to respond to an event for at least 30 minutes but some events may last longer. Before electing you to take part, your provider checks how long the event will last and that your battery can cover the entire period.
Do I need a half-hourly meter to take part in DFS?
Yes. Your provider needs meter readings for each half-hour period so it can compare how much electricity you took from or sent to the grid during the event against your baseline. A baseline is the amount of electricity your business was expected to take from or send to the grid during the same period. Most commercial sites must also have half-hourly settlement, although there are some exceptions. Providers check whether your meter meets the rules before signing you up.
Is there a minimum battery size for the Demand Flexibility Service?
NESO’s minimum DFS unit size is 0.1 MW, or 100 kW. This refers to power, not the amount of electricity the battery can store. In simpler terms, your battery, or a group of batteries combined by your provider, must be able to change grid use by at least 100 kW.
Your battery does not have to provide the full 100 kW on its own. A provider can combine it with batteries at other businesses to reach the minimum.
Can smaller commercial batteries take part in DFS?
Yes. An aggregator or virtual power plant operator can combine several smaller batteries into one DFS unit if, together, they provide at least 100 kW. The batteries grouped within one unit must also be in the same DFS zone, which is one of the geographical areas NESO uses to organise events.
Can my battery charge during a DFS event?
Yes. During some events, NESO may ask businesses to use more electricity because there is more power available on the grid than currently needed. If this is the case, your provider can respond by charging up your battery. When there is less power than needed, it might instruct your battery to discharge so you take less from the grid from your site.
Do I have to take part in every DFS event?
No, and the chances are that your provider will not enter you into every event. That’s because they check what your business needs the battery for and whether another use could save or earn you more money. Sometimes, taking part in an event may not provide the best value for money, for example when you need to keep the battery charged to avoid expensive grid use later.