What is a Distribution Network Operator? (DNO)

What if my Distributor ID isn't on the list?

You're probably connected to an Independent Distribution Network Operator (IDNO). These look after smaller networks, often on newer developments that connect into the main regional network. They do the same job for your site, and 105 will still put you through to the right one.

What to do in a power cut

Call 105. It's free from most landlines and mobiles in England, Scotland and Wales, and it connects you straight to your DNO. In Northern Ireland, call NIE Networks on 03457 643 643.

You can also call 105 if you spot damaged power lines or a damaged substation. There's more on the service at powercut105.com.

Your supplier can't fix a network fault, so calling them first just adds a step. And if you weren't sure who your DNO was, you're in good company. When 105 launched, ENA research found that only 11% of people who'd contact their network operator in a power cut could name it.

Why your DNO matters for your business

Most of the time, you won't think about your DNO at all. But there are four moments when knowing who they are, and what they owe you, makes a real difference.

If a power cut goes on too long

Ofgem sets standards for how quickly DNOs have to get the power back on. If they miss them, you're owed a payment, and businesses on a business energy contract get more than homes do.

In normal weather, the time limit is:

• 12 hours, if fewer than 5,000 premises are affected
• 24 hours, if more than 5,000 premises are affected

You'll get a further payment for every extra 12 hours without power. There's also a separate payment if your business loses power more than four times in a year, for at least three hours each time. Severe weather has its own, longer time limits.

Payments are usually made automatically, by cheque to the affected premises. They can't go on your energy bill, because your DNO doesn't have access to your supplier's billing details. See the ENA's guide to power cut compensation.

If you need more power

Every business connection has a set capacity, measured in kVA. It's the most electricity your site has agreed to draw at once, and it's often shown on your bill as your agreed or assigned capacity.

Planning to expand, add heavy machinery or install EV chargers? Talk to your DNO before you buy anything. They'll check what your connection can handle and, if you need an upgrade, quote you the cost and timescales. Accepting and paying that quote secures the capacity for you.

It's worth starting early. Upgrades take time, and regularly going over your agreed capacity can mean extra charges.

When you read your bill

Your DNO doesn't bill you, but its charges are on your bill. They're called Distribution Use of System charges, or DUoS. They pay for running and maintaining the local network, and your supplier passes them on to you. They sit alongside TNUoS, which covers the national transmission network.

For some business connections, such as those with half hourly meters, DUoS rates change with the time of day, using red, amber and green bands. Red is the most expensive. It usually covers weekday evenings, around 4pm to 7pm, though the exact times vary by region. If you can move flexible energy use outside those hours, you could cut that part of your bill without using any less.

If there's network equipment on your land

If your business owns land with poles, cables, power lines or other network equipment on it, you're likely to have a wayleave agreement with your DNO. It gives them the right to install, access and run that equipment safely.

In return, the landowner gets an annual payment, made in arrears and based on the type of equipment and its impact on the land. If the equipment gets in the way of farming, compensation may be paid too.

If you have a question about a wayleave, or think you should be receiving payments, contact the wayleave officer at your local DNO. The ENA's wayleaves guide has more detail.