A headteacher was shocked to find out his school's energy bill is set to soar by a staggering £95,000.
Niall Smith, 51, said the electricity at Southborough High School, Surbiton, in Greater London cost £55,000 this academic year.
However, when the estimated bill from Opus Energy landed on his desk on June 27 it showed it would be an estimated £150,000 for the next school year.
He said "someone somewhere is making a lot of money" which he argues would be better spent investing in children's education.
At his school, it would be used on two extra teachers, or four teaching assistants - or news buildings, classrooms, toilets and teaching resources.
The teacher from Godalming, Surrey, said: "It's an important issue that needs to be publicised and addressed.
"These are public funds from the taxpayers, earmarked for the education of children.
"But this additional £100,000 is not going to have any educational benefit whatsoever.
"I want to know where the taxpayers' money is going.
"We are a single academy trust that operates on our own - essentially a small ship on a big sea."
Niall, who has been headteacher at the 820-student all-boys state comprehensive school for 10 years, added: "That kind of money could do so much for the school in a variety of ways.
"£100,000 could afford two teachers or four teaching assistants.
"If you consider some of our new and younger students who have been very badly affected by the lockdowns - this kind of support could be crucial for them.
"It could be spent improving the fabric on buildings, toilets, educational resources, the list goes on."
Niall said the school has gone through a "rigorous" process to investigate the issue - but this deal is the best they were able to obtain.
He says Southborough High School has been on a fixed contract with Opus Energy and Total Gas and Power - but their current contract expires in September.
Upon receiving the estimated bill, Niall said: "I was shocked, our governors were shocked and our senior leadership team shocked.
"The way we had to fix our contract was very high pressure.
"We got a spot price for the contract that remained stable for one day - but we had to decide then and there because otherwise, the cost could fluctuate a day later.
"Schools are then exposed to that risk of making a poor decision and they should be offered protection or invention from regulators - and given a fair price.
"Given the scale of the system, lots of small schools or single academy trusts will be ripped off.
"I'm not absolutely certain that power and energy companies could offer cheaper prices.
"But the inequalities between people on fixed and unfixed deals are apparent and some intervention is required.
"I feel the public sector generally are at risk of over-paying for electricity or possibly being ripped off.
"Despite the extortionate bill figures - we have a great business manager and very capable governors.
"Other public sector outlets might not have that.
"The government need to intervene here because the public sector desperately needs protection."
The school are actively looking into energy-saving strategies, but fears larger projects are not going to provide immediate solutions.
"In terms of energy savings, we are fully committed to that going forward," he said.
"We are actively investigating solutions like light bulb replacements but the issue with bigger projects such as solar panel installation is that they need upfront investment.
"We are all for it, but they often require very complex financial arrangements - and as a small singular academy trust, we have to do our homework first."
An EDF statement said: "EDF was asked by the customer’s energy broker to be part of the tender. The process was to offer a contract with an effective start date of 01 October 2022.
"As part of the process, we were provided with actual consumption information for the customer’s electric and gas supplies.
"EDF issued a quote to the broker for a 24 Month contract, this provided an illustration of the cost the customer should expect over the course of the contract, based on the information supplied to us by the broker. This illustration is provided to allow the customer to make an informed choice before entering into the contract which has since been signed by the school’s Business Manager.
"The prices outlined in the contract are bespoke to the customer and are in line with current market trends. We do appreciate that energy prices have risen significantly since the school will have last entered into a contract 2 years ago. All invoices will be based on the customer's actual usage, where available, and may be less than the indicative amount shown on the tendered quotation."