United Kingdom

The watchdog said that in previous winters some electricity generators had deliberately stopped generating power early in the afternoon, meaning plants were switched off during the crucial evening spike in demand. They would then offer to resume generating power later in the day, cashing in on the greatly increased prices on offer via the balancing mechanism.

Sounds rather similar to the behaviour of a little energy company based in the USA called Enron:

After the passage of the deregulation law, California had a total of 38 Stage 3 rolling blackouts declared, until federal regulators intervened in June 2001. [...] Subsequently, Enron traders were revealed as intentionally encouraging the removal of power from the market during California's energy crisis by encouraging suppliers to shut down plants to perform unnecessary maintenance, as documented in recordings made at the time. These acts contributed to the need for rolling blackouts, which adversely affected many businesses dependent upon a reliable supply of electricity, and inconvenienced a large number of retail customers. This scattered supply increased the price, and Enron traders were thus able to sell power at premium prices, sometimes up to a factor of 20 × its normal peak value. https://en.m.wikipedia.org/wiki/Enron

It’s absolutely ridiculous that something so important and universally required is in the hands of corporations. It’s like a hyper capitalist dystopian novel. Future generations will look back on this in bewilderment.

Wrist slapping to occur. Maybe an apology and some remorse. They don't care and will do it again until regulated

This is the best summary I could come up with:

Electricity companies will no longer be able to deploy a controversial tactic that forces up bills at the expense of consumers, the energy watchdog has said as it unveiled rules designed to curb firms making “excessive” profits in the winter.

The “balancing mechanism” is the main tool used by the National Grid electricity system operator (ESO) to plug gaps between supply and demand on the network.

It allows the ESO to do deals with generators at short notice to ensure the right amount of electricity supply to maintain relative equilibrium on the grid, preventing imbalances that can cause problems such as power outages.

Annual balancing costs tripled in the winter of 2021-22, as power prices surged to record highs, rising to £1.5bn compared with an average of £500m in the previous three years, Ofgem said.

Ofgem said the new Inflexible Offers Licence Condition (IOLC), which comes into effect on 26 October, would ban this practice and would apply to any generators that switched off their plant for more than an hour.

The actions Ofgem’s new rules are designed to prevent were not in breach of electricity generators’ licence conditions at the time they took place.

The original article contains 724 words, the summary contains 195 words. Saved 73%. I'm a bot and I'm open source!

Just a cost of business, so no problem. If the consequence is a fine, then it isn't illegal.