The decarbonisation of transport

The decarbonisation of transport

Today, transport is one of the largest energy uses globally. The sector uses huge amounts of energy in which to power it, resulting in huge levels of harmful emissions being generated, which cannot be sustainable. Rebecca Markillie from ITM Power discusses how hydrogen is being used to address this.

The energy available to us is changing, with more and more renewables, and it is providing the option for a clean energy supply. The challenge comes when trying to join this intermittent energy to a sector where energy is needed constantly and in a reliable fashion.

There is a change happening with consumers being more aware of energy uses and looking at different transport options and alternatively powered vehicles.

The main change which has already taken place is an increase in electric vehicles (EVs). But with the increase of EV recharging, it has however brought about a larger headache for electricity providers whose job it is to balance the electricity grid. With many small loads being connected and disconnected in an unscheduled manner, it results in more fossil fuels being used in gas/coal fired generators, to generate instant electricity to keep the lights on elsewhere. 

Renewable electricity is very hard to predict and is an intermittent input into the grid, and cannot be relied upon alone to keep the electricity grid balanced. Hydrogen can offer a solution in the form of energy storage.

The cleanest way hydrogen can be produced is using an electrolyser. This can respond to a quick, intermittent burst of renewable electricity, and by adding water, it splits the water into hydrogen and oxygen.  

The hydrogen can then be stored for long periods of time and used to refuel fuel cell electric vehicles (FCEVs) at either 350 or 700 bar pressure, which would take around 3-4 minutes to refuel, and then enable the vehicle to travel 300-400 miles. 

The electrolyser can just sit and take excess renewable electricity as a scheduled load, when the electricity provider needs to use up the intermittent burst of electricity. This eliminates unscheduled loads being placed on the electricity grid, keeps it more stable and prevents the further fossil fuels from being used.

A number of car companies have developed FCEVs and from March 2019, there will be five different models available from Toyota, Hyundai and Honda.

Following on from their success with the Prius, Toyota have now moved onto the future, with their appropriately named ‘Mirai' (which means Future in Japanese). The Mirai benefits from the tried and tested electric drivetrain of the Prius, but with the added benefits of a fuel cell, which uses the hydrogen to generate electricity on board the vehicle, acting like a range extender and allowing the Mirai to do 500km on one tank (5kg) of hydrogen.

Toyota are not alone in offering FCEVs. Hyundai were the first in the UK to offer the ix35 Fuel Cell vehicle, and are already marketing their next model - the Hyundai Nexo - which should go on sale in early 2019. The Nexo boasts an increased range (756km) as well as a higher efficiency fuel cell (60%). Honda are also in the hydrogen club, with their Clarity, which has not yet made the UK market, but is a huge hit in the US, where the cars can be leased for $199/ month. If the owner is based in California, the driver can use the ‘carpool' lanes, avoiding the traffic queues. Incentives like these are yet to be seen in the UK.

Hydrogen also offers the ability to improve air quality, as when generated in a green way, it does not use fossil fuels in its generation or in its distribution, as the gas is generated on-site. You start with water, and finish with water. Hydrogen really is the only clean fuel option we have.

DISCUSSION

Gaslines 550x250

The natural gas grid could provide the key to unlock the long talked-about potential of the hydrogen economy says Henri Winand.

2hydrogenforheat 550x250

The Institution of Mechanical Engineers has called on government and industry to boost investment in technology to promote the use of hydrogen as a way of storing energy.

2hydrogenforheat 550x250

An All-Party Parliamentary Group on hydrogen has been setup.