New engine to slash 50% off emissions
A Cambridgeshire firm’s new engine technology, reportedly capable of reducing CO2 emissions by 50 per cent, could become a commercial reality following a £40k award to develop a prototype.
Epicam has broken cover after winning a national competition, ‘Springboard,’ set up by Shell to reward the most innovative and commercially viable ways of reducing CO2 output.
Current engine technology only takes advantage of approximately 20 per cent of the energy potentially made available by burning fossil fuels, with 30 per cent of the valuable energy being wasted as heat.
Epicam believes its ‘dexpressor’, which harvests this wasted heat, could improve the efficiency of the engine, thus decreasing the amount of CO2 released into the atmosphere by up to 50 per cent.
The dexpressor works on a similar principal to a turbocharger, harnessing energy associated with the engine’s exhaust and translating it into mechanical energy.
But where a turbo uses an impeller inside the exhaust manifold to drive a pump, Epicam’s technology collects the waste heat emitted by the exhaust and uses it to drive a pump-like rotor.
As a combustion engine runs, it produces hot exhaust gases which leave the engine system via the exhaust pipe. Engineers regard the heat produced by the engine as ‘low-grade,’ i.e. not sufficiently intense to be productive.
The unique technology, currently a computer model pending the development of a working prototype, accumulates and utilises this ‘low-grade’ energy in a closed system, heating water via a heat exchange coil around the exhaust manifold of the engine.
The water in this system is super-heated to around 370°C, past the stage of steam, becoming ‘super-critical water’ and building up 1000 bar of pressure. The pressure is used to turn two rotors, via an innovative pressure retention system, a pair of “low friction rotating devices.”
One of these rotors feeds into the crankshaft of the engine, lending its power to turn the wheels of the car.
It is the method of keeping the high pressure created in the system and using it to turn the crank that is the secret behind Epicam’s invention. The help given to the engine in turning the crank could translate into being able to reduce the capacity of the engine by up to 50 per cent; so less capacity equals less fuel burnt which in turn would create lower carbon dioxide emissions.
The £40k award will now give Epicam the financial capability to translate its dexpressor idea from a computer model into a working example of the technology, which the firm expects to complete in four to six months.
“This award is a strong endorsement of Epicam’s innovative approach to CO2 reduction and will help the company to fund the development of a working prototype for demonstration to engine manufacturers later this year,” said Tony Dye, Epicam’s MD.
The automotive industry is the entry point for the technology, according to Peter Howarth, who is working with Epicam on its business strategy. “But the technology could also be employed on a powerplant, or any system similar to an automotive engine which generates heat, and runs a driveshaft,” said Howarth.
The company is extremely hopeful about the potential of the innovative design, but doesn’t yet have any offers from the automotive industry – “not at this early stage,” Howarth said.