New Rolls-Royce Engines Are CO2-Free

The new Rolls-Royce engines are powered by gaseous hydrogen and are ready to be tested.

Going Green

In July, Britain’s well-established engine maker officially joined forces with European’s leading economic airline easyJet, to achieve the net-zero emission goal by 2050. The two companies contribute to H2Zero – the initiative that focuses on sustainability through hydrogen.

Today, Rolls-Royce and easyJet are testing out their two supreme engines, AE 2100 turboprop and Pearl 15. The aim is simple; to prove that hydrogen can efficiently and safely power small to mid-size commercial aircraft.

This officially brings aviation one step closer to becoming a zero-emission industry.

The initial ground test successfully shows that a business jet can run on hydrogen-based fuel at low speed while emitting minimal to zero amounts of carbon dioxide (CO2). With this promising result and more upcoming tests, Rolls-Royces expects to put completely carbon-free, hydrogen-power flights in service by mid of the 2030s.

Hydrogen Fuel: What’s the catch?

Hydrogen can be used as a jet fuel and electrical power source for hybrid and all-electric planes. But the catch is in storage and volume limits; a plane needs to store hydrogen at critical -253°C (-423.4°F) to preserve the liquid form of the fuel, and liquid hydrogen takes about four times the space of the same amount of kerosene fuel. Moreover, it takes approximately 3,000 liters of gaseous hydrogen to get the same energy as a liter of kerosene at atmospheric pressure.

Rolls-Royce states that it is confident about using hydrogen fuel to power short-haul services; however, for the long-haul ones, the best eco-friendly option as of now is undoubtedly sustainable aviation fuel (SAF).

Black, Blue, and Green Hydrogen

Hydrogen fuel does not give off CO2 while it combusts to power an engine, but it does not mean that this type of fuel is entirely eco-friendly.

The color terms green-hydrogen or blue-hydrogen refer to how the gas is produced; blue-hydrogen is made from natural gas through a process called steam reforming, which releases CO2 as a by-product. Black hydrogen, on the other hand, is on the opposite end of the eco spectrum since this process involves black coal and lignite. (See The Hydrogen Colour Spectrum)

Rolls-Royce is using green hydrogen.

The AE 2100 uses the gas produced from water using electricity – electrolysis – at the European Marine Energy Centre in Scotland. The electricity is generated by waves and wind, and the by-product is oxygen – which makes the entire process incredibly clean.

Are Rolls-Royce Engines the First to Run On Hydrogen?

The AE2100 and Pearl 15 are not exactly new in air transport. The AE line is one of the top-notched dependable engines, and to date, there are more than 1,800 AE engines in services such as the US Air Force and the Japanese sea rescue unit.

Pearl 15 was launched in 2018, and it is Rolls-Royce’s proudest and most advanced family of engines for commercial flights.

Rolls-Royce and easyJet chose to run the test with these two engines for their most valued features; AE2100 is highly durable and reliable, and Pearl 15 has a cooling system that increases fuel efficiency.

But they are not the first group to use hydrogen as jet fuel.

Earlier this year, Airbus officially tested its first hydrogen combustion technology on an A380 engine. The test is a crucial part of the ZEROe mission, whose aim aligns with Rolls-Royce’s H2ZERO. Airbus also expects to deliver a fully ready and mature hydrogen system by 2025.

Can hydrogen fuel change the face of alternative energy? Let us know what you think in the comments.