A Royal Navy sailor who served on nuclear ‘Hunter Killer’ submarines has used his military know-how to develop a new ‘green’ car device to slash motorists’ fuel bills and harmful emissions.

Former Leading Seaman Brian Sheard, 49, has switched from Cold War warrior to civvy-street inventor to create – in his own garage – a smart box inspired by the way submarines make their own air to keep crews breathing during long missions underwater.

His resulting compact hydrogen fuel-cell box reduces car emissions by up to 80 per cent and offers fuel savings of up to 20 per cent, according to independent tests.

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Inspired: Former Royal Navy submariner turned inventor Brian Sheard

His box fits neatly into a car’s engine bay and uses electrolysis to generate on-board hydrogen.

This is pumped immediately and directly into the engine to make the petrol or diesel fuel burn faster, cleaner, and more completely.

Having designed, developed and tested the device in his garage and on the road over eight years using his own family cars, Mr Sheard sought professional help from industry and finance from crowd-funding to found his company called CGON, which now manufactures his ‘green’ box in the UK.

HOW IT WORKS CGON’s ‘ezero1’ is a compact electrolyser box fitted into a car’s engine-bay. It produce hydrogen which goes directly into a petrol or diesel engine’s fuel/air mix for a cleaner and faster burn that slashes fuel costs and pollution. The box uses electrolysis - the decomposition of a liquid using electricity - to create a small amount of very pure, powerful hydrogen (called Ortho Hydrogen) , on demand. It is inspired by nuclear submarines, which use industrial-scale electrolysis to break down water (H2O) to create oxygen - to allow crews to breath while staying underwater for weeks at a time - with hydrogen as a by-product. Inside the box are two special titanium-coated electrodes - a cathode (negative) and anode (positive) – which pass electric current through an electrolyte solution, causing hydrogen gas to split off. The hydrogen is ‘sucked’ into the engine’s combustion chamber along with the conventional fuel-air mixture. This creates a faster, more complete and ‘cooler’ burn that eliminates almost all waste gases, gives better fuel economy, and ‘drastically reduces’ harmful emissions including Carbon Dioxide, Carbon Monoxide, NOX, Hydrocarbons and particulates. 80 per cent reduction in overall emissions and about 20 per cent reduction in fuel consumption. It also keeps diesel particulate filters clean. System works with any petrol, diesel, or LPG internal-combustion engine including cars, taxis, forklifts and HGV trucks, and is on trial with car-maker Morgan.

It has already caught the attention of Malvern sports car-maker Morgan, which has been trialling the kit in its own cars.

The married father-of-two’s technology is a peace-time spin-off from his Cold War Royal Navy job when - as well as tracking Russian submarines and ships on sonar - he was responsible for creating an on-board oxygen supply, through electrolysis, so his crew didn’t suffocate while serving underwater for weeks at a time.

Then, the hydrogen was a waste by-product that was not needed, so was jettisoned.

But in his new device, that hydrogen is now harnessed.

Mr Sheard developed his device in the garage of his modest three-bedroom semi-detached home in Topsham, Exeter, where he lives with his wife Dawn. The couple have two grown up daughters: Penny, 26, and Molly, 23.

Born in Woking, Mr Sheard grew up until age nine in South Africa before moving to Bristol and joined Navy in 1986 age 17, training in Gosport and serving in diesel-electric and then Hunter Killer nuclear submarines before leaving the service in 2008.

Explaining how his life beneath the waves had sparked his idea, the former submariner said: ‘My primary role was Underwater Acoustic Analysis, so I was a sonar specialist. But being a submariner, you need to know every other job on board, including knowledge of mechanical systems, in case you are caught in a compartment in time of emergency.

‘One of those systems was the sub’s on-board electrolyser. This takes in sea water, splits it into hydrogen and oxygen. The oxygen is used for life support on board, while the hydrogen is discharged overboard.’

He said: ‘It was only when I left the Navy that it dawned on me that I could apply my knowledge of electrolysers to hydrogen additive systems in cars.’

Significantly, he has created specially-coated titanium electrodes and an electrolyte solution that does not create toxic bi-products (such as Hexavalent Chromium ) during the electrolysis process.

The flagship ‘ezreo1’ device for cutting car pollution is about the size of a tablet computer and is fitted inside the car’s engine bay

CGON managing director Simon Johnson (left) with device inventor and former Royal Navy submariner engineer Brian Sheard (centre) as a technician look on

A key breakthrough came when he perfected the chemical reaction to produce a specific type of hydrogen called Ortho Hydrogen, whose burn characteristics suit the combustion cycle in an engine.

Mr Sheard said: ‘I became a bit of a chemist and identified a material that didn’t leach any bi-product’.

He used his Vauxhall Combo van and is wife’s Vauxhall Corsa supermini for development work, as well as two Fiat Puntos belonging to his mother and his brother.

Once he had created a working prototype he sought business partners and investors to help make his idea a commercial reality, hooking up with businessman Simon Johnson who is now the firm’s managing director.

Mr Sheard said: ‘Funds were tight, but all my spare time, in my garage, was spent on putting the technology together. The next stage was to get more money.

‘I went to a crowd funding platform called Crowd Cube, raised £150,000 in exchange for 10 percent of equity. That money allowed me to further develop the product.’

Mr Sheard said of the pressure his dream has put on his family: ‘My wife has been through the mill on this. She’s very tolerant indeed. ‘It’s been a long journey to get where we are now. But I’m very happy and excited. It’s a rollercoaster ride. Sometimes it’s elation, sometimes I’ve been on a low. But I’ve never been afraid of failure. This product has been my hobby and my job ever since I left the Navy.’

Sheard developed the system using his know-how from creating an on-board oxygen supply on submarines (like the one pictured above) through electrolysis, which stopped his crew from suffocating while serving underwater for weeks at a time

Ex Royal Navy submariner turned inventor Brian Sheard (left) and CGON managing director Simon Johnson (right) review independent on-board emissions test data for their new product

Emissions achieved on cars fitted with submariner-turned-inventor Brian Sheard’s ‘e-zero’ device were tested in the real world on the road by independent Emissions Analytics using their mobile testing kit

There are three variants of his device: for passenger cars and vans; for smaller coaches and light goods vehicles up to 7.5 tonnes; and for heavy goods vehicles and buses.

The flagship consumer version for motorists – called ‘ezero1’- costs £459 (including VAT and fitting), can be fitted to any internal combustion-engined car in about an hour, and comes with a 12-month guarantee.

It was independently tested by experts at Emissions Analytics whose ‘real world’ performance tests use a portable device, which measures emissions coming out of the exhaust pipe while cars are driven. For urban driving, the testing showed reductions of 91.3 per cent in particulates or ‘soot’, and a halving of nitrous oxides (47.9 per cent reduction in NOx and a 50.6 per cent reduction in NO2).

CGON chief executive Simon Johnson said: ‘Air quality, especially in cities, is one of the great challenges of our time.

‘Over 100,000 cars fail their MoT each month on emissions alone in the UK. This technology tackles this problem head-on by reducing particulates and NOx.’

‘We have completed testing of hundreds of vehicles at certified MoT stations and recorded an average 80 per cent reduction in overall emissions.

‘Less fuel is also used with real-world drivers reporting savings of up to 20 per cent.’

The box doesn’t store inflammable hydrogen on-board but instead creates small amounts of the gas ‘on-demand’ from the electrolyte solution. The box is topped up every 6,000 miles using the firm’s patented electrolyte solution costing £5 for a 250ml pouch.

Experts said consumers should tread carefully and check that their insurance and warranties are not invalidated by fitting such hydrogen fuel additive devices.

CGON itself advises all customers to advise their insurance companies but says: ‘From feedback most companies just thank their policy holders for informing them.’

A number of companies produce similar devices but they are not yet widespread. And the extent of their effectiveness is the source of much debate on expert forums.

A bottle of the special electrolyte solution used inside the ‘green’ device. The liquid is broken down through electrolysis to liberate hydrogen which helps the car’s engine burn petrol and diesel fuel more efficiently, reducing pollution and fuel costs

AA spokesman Ian Crowder said: ‘The scientific principle behind this technology is well established, though this particular system seems to be be doing things in a new way.

‘But motorists should tread carefully. There is a risk you might invalidate your car’s insurance or its warranty, particularly on a new vehicle.

‘Some insurers will not allow it and others will seek more information. ‘Manufacturers are protective and often do not like people fiddling with their cars – even if it improves them. However it is interesting that Morgan are trialling the equipment.’

Morgan Motor Company’s technology director Graham Chapman said the Malvern-based car firm were in a ‘collaborative partnership’ with CGON with a view to fitting the devices to its new cars from the factory, and retro-fitting them to existing cars: ‘We have been testing CGON’s ezero1 product over recent months and have found a significant difference in both emissions levels and MPG.

‘We are hopeful that the product will become part of our products in the near future, leading to savings in CO2 and fuel consumption for our customers.’

Morgan said the system enhances its ‘green credentials’.

The Society of Motor Manufacturers and Traders (SMMT) – of which CGON is a member – said consumers should always check with the car-maker: ‘Retrofitting may change compliance with the vehicle’s original type approval and might invalidate a new car’s warranty. They should check first. Car manufacturers spend millions of pounds on engine development so anything that might interfere with their performance could be a concern.’