A lobbyist who has worked with Conservative MPs to argue that the development of as yet unproven fuel additives means it is unnecessary to phase out petrol and diesel engines is the director of a firm developing such products, it has emerged.

Howard Cox, who runs the FairFuelUK campaign, is heavily involved with the all-party parliamentary group (APPG) on fair fuel, which recommended last year that ministers urgently look at fuel additives, saying these reduced emissions by more than 50%.

An investigation by the environmental research group DeSmog has found that Cox is one of two directors of a company called Ultimum, which markets an additive that it describes as “the 21st-century vehicle emissions solution”.

Cox was heavily involved in the all-party group report, which argued that the government should drop its proposed ban on new petrol and diesel cars and vans from 2030, citing a series of reasons. His commercial interest was not listed.

The other Ultimum director is the former Liberal Democrat MP Lembit Opik, who works with a motorcycling campaign group and was quoted in the report.

Cox told the Guardian he rejected any conflict of interest, saying he supported fuel additives, known as catalysts, anyway and was unlikely to make any money from the venture.

However, the revelation raises more questions about the connections of some Conservative MPs who are vocally querying the government’s net zero and wider green policies, including the phasing out of petrol and diesel vehicles.

Craig Mackinlay, the Conservative MP who chairs the all-party group on fair fuel, also heads the new Net Zero Scrutiny Group (NZSG), which climate scientists have accused of seeking to derail green policies by arguing they are too damaging to the cost of living.

A series of other NZSG members are either also members of the all-party fair fuel group or gave supportive quotes for the report, including the Tory MPs Robert Halfon, Steve Baker, Philip Davies, Karl McCartney and Andrew Bridgen, and the peer Peter Lilley.

The all-party group, which is funded by the logistics and freight industry, has worked closely with Cox in successfully pushing for fuel duties to remain frozen since 2010.

There is also controversy about claims Cox has made for additives in general and for the one his company is marketing. The Ultimum5 website says it reduces nitrogen oxides emissions by between 22% and 94%, and particulate matter by 25% to 100%.

The results are based on what the company called “real-life field tests” in countries including the UK, US and South Africa, although it is not clear who carried out the tests.

Alastair Lewis, a professor of atmospheric chemistry at the University of York and an expert on air quality, said additives could help improve engine performance and had been used for decades. “However, they come at a cost, from the extraction of the raw materials through to the synthesis of chemicals, their packaging, sales costs and so on,” he said.

“What is often lacking, however, is quantitative data that shows just how much of an improvement they bring. Small marginal gains in environmental performance in the engine could be wiped out by the full lifecycle cost of making the additive. The marketing of additives often includes lengthy descriptions of plausible-sounding chemistry, but virtually never includes independent test data that shows improvements in performance in the real world.”

Macklinlay said he was aware of Cox’s involvement in the company, adding: “His activism with FairFuelUK is completely unrelated in my view and not linked to potential profit elsewhere.”

In a statement, Cox said: “There is no conflict of interest whatsoever. I asked the APPG to include in the fossil-fuelled car 2030 ban report, to put into the public domain as a logical recommendation from thousands of FairFuelUK supporters, the need to look at alternative solutions to lowering emissions and to reduce fuel consumption.

“I personally felt so strongly that the government are ignoring practical, effective, available ways to improve air quality, I chose to put my effort into one of the more promising fuel catalysts. No money has been invested or any money taken out or likely to be.”

Cox said he was being targeted for unfair personal attacks “by ignorant DeSmogites”.

Extracted in full from: Lobbyist opposed to UK petrol cars ban is director of fuel additive firm | Travel and transport | The Guardian