Market Watch  ·  Issue 5  ·  Tuesday 28 July 2026

Watts Happening

 

The UK energy newsletter that doesn't work for the industry

The Spark

VAT on domestic electricity is about to hit zero. From 1 October it drops from 5% to nothing and holds there until spring.

It is Andy Burnham's first big move as Prime Minister, funded by scrapping the planned £1.8bn digital ID scheme. The saving is about £45 on a typical yearly bill.

Then the small print. Cornwall Insight already expects that £45 to be wiped out by the October price cap, which is forecast to climb again at the same moment the cut arrives. Breathing space, not a rescue.

This Week in Watts

The grid operator is being investigated for allegedly hiding how close June came.

In Issue 4, at the start of the month, we noted in passing that NESO, the body that runs Great Britain's electricity system, had issued an Electricity Margin Notice during the June heat. A margin notice is a request for more generation. It is routine. We moved on. The story did not.

On 7 July the Shadow Energy Secretary, Claire Coutinho, wrote to the government with allegations from a whistleblower inside the operator. On 15 July she put them to the Commons. There are three. That on 23 June the operator failed to meet the grid security standards designed to prevent blackouts. That its corporate affairs team interfered with operational decisions, putting the operator's reputation above security of supply. And that decisions were being logged in live documents with no audit trail.

These are allegations, raised by a politician citing staff, not findings. Hold them at that weight. But they are being taken seriously by the people who would know if they were baseless. On 13 July NESO commissioned the law firm Eversheds Sutherland to investigate. Ofgem has used its licence powers to commission its own review of the June event and is overseeing the independent one. Staff can give evidence anonymously through a panel, which matters, because a whistleblower who has to identify themselves usually goes quiet.

NESO's position is that the system operated securely throughout, with no disruption to customer supply. That may well hold up. Worth setting beside it: Hansard records an MP whose constituents reported intermittent blackouts that same week. Both statements are on the record now. The investigation exists to work out which one the evidence supports.

Here is why it lands on you. Every heat pump and every EV charger added to a home leans harder on this system. Part of the value of a battery behind your own meter is that it does not care whether the control room had a bad week in June. The rest of us are trusting a number we are handed. This summer, someone inside the room said the number was wrong.

Storage behind your own meter is worth most on the days you are told nothing went wrong.

The Bill Buster

Plug-in solar is finally legal. The kits in the shops still don't qualify.

From 27 August, a new statutory instrument lets you plug a solar setup of up to 800W straight into a standard socket, no electrician required. For renters and flat-dwellers who have never had a legal route to their own generation, that is a real change.

Two catches before you buy. The rules cover panels and a microinverter only. Any device with a battery is excluded, and many plug-in kits sold today pair the panels with storage. So the products marketed as the easy route often aren't the ones this rule actually clears.

Second, if you already have roof solar, adding 800W can push you past the 3.68kW limit for simple connection and into a full G99 application with your network operator. That is weeks, not minutes.

Worth doing. Worth doing with your eyes open.

→ Read the regulation before you buy: SI 2026/848

Watts on the Market

Unsold this week  ·  Reader resource

This week made the point better than we could. A tax cut arrives, the cap rises to meet it, and the net position barely moves. Government relief is a patch. It is not a plan.

The one number most energy decisions skip is what staying exactly as you are costs you over 25 years, at realistic inflation, with nobody selling you anything at the end. That is what the Watts Happening Cost of Inaction calculator works out. Your bill, your property, two scenarios, one number.

→ Run your 25-year number at calculator.wattshappening.energy

Quick Watts

Solar PPAs

The Department for Education is piloting private power purchase agreements on up to 150 schools: a third party installs and maintains the panels, the school buys the power, nothing paid upfront. From 15 July, any school-estate PPA must use DfE's standard template. Watch the model. It is coming for commercial roofs next.

(GOV.UK, 16 July 2026)

£2,500, unclaimed

The Boiler Upgrade Scheme offers £2,500 towards an air-to-air heat pump. The latest scheme figures show 62 applications and not one voucher issued. A grant that exists on paper and nowhere else. Do not build a plan around it.

(BUS statistics, May 2026)

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