Monday 5th Dec 2016 - Logistics Manager

The hard cell

There are now cars, buses, trucks and forklifts using fuel cell technology, but, says Malory Davies, while the technology is developing rapidly, the infrastructure to support it is lagging behind.

First published in Logistics Manager, April 2015.

First published in Logistics Manager, April 2015.

If you thought fuel cell technology was years away, think again. Toyota will happily sell you a fuel cell powered car today – if you’ve got £38,000.

Toyota launched the Mirai in November last year which uses both fuel cell and hybrid technology.

The fuel cell stack has a maximum output of 114 kW giving the car a range of about 400 miles. It can be refuelled with hydrogen in about three minutes.

But in the first month of sales in Japan it received 1,500 orders, and is soon to launch in the US and Europe. So Toyota is now planning to ramp up production much faster and will produce 700 cars in 2015, 2,000 in 2016 an 3,000 in 2017.

Having put a fuel-cell powered car onto the market, Toyota is now working with Hino on a bus using the technology. The bus is currently being tested on the Oiden bus route in Toyota City. It is equipped with eight high-pressure hydrogen tanks as well as two fuel cell stacks and two motors to provide increased output. It also features a system for supplying electric power to buildings and other facilities during emergencies.

In France, Renault Trucks and La Poste, the French post office, are testing an electric truck equipped with a hydrogen fuel cell that doubles its range to 200 kilometres.

The 4.5 ton Maxity electric truck will be tested for the next year under operating conditions at Dole in the Jura region. The fuel cell has been developed by Symbio FCell.

Maximum power

Christophe Vacquier, who supervises the project, said: “When the vehicle is running, the electric motor is fed by two complementary energy sources; the fuel cell is capable of delivering a maximum power of 20 kW and, once that threshold has been reached, the batteries kick in to supply whatever power is still required. When idle, the fuel cell is available to recharge the battery as needed.”

The heat released by the cell is then reused to warm the passenger compartment, which avoids having to consume any energy stored in the batteries, thus helping ensure longer autonomy.

“The formation of water from oxygen in the air and hydrogen stored in the tanks triggers the production of electricity and heat, in accordance with the reverse principle of water electrolysis,” said Vacquier.

The test route in Dole route is mainly rural and covers a distance of some 70 km. The vehicle has a maximum range of 200 km and a top speed of 90 kmph. It has an authorised gross weight: 4.5 tons, certified in France at 3.5 tons + 1 ton, by virtue of special regulations favouring “clean-burning vehicles”.

“Hydrogen stands out today as an efficient solution for extending the possibilities of the electric vehicle product line and its autonomy. More broadly, the development of a hydrogen-based energy storage system is a linchpin to our energy transition”, said Frédéric Delaval, technical director of the mail and package delivery services office at La Poste.

But these are not the first fuel cell vehicles on the road, Korean car maker Hyundai claims that honour for its ix35 Fuel Cell car which went into series production in 2013. It is reported to have sold 200 world-wide. However, the vehicle was very expensive and it was reported from Korea that Hyundai recently cut the price, in the face of competition from Toyota’s new offering.

One of the issues in the development of fuel cell vehicles is access to fuel. The fuel cell needs hydrogen and there is little or no infrastructure currently available. Toyota says that sales plans for Japan, the US and Europe following the production increases will be formulated taking into consideration each region’s level of hydrogen infrastructure development, energy policies, car-purchasing subsidies, consumer demand, environmental regulations, and other factors.

In Japan, Toyota is working with Nissan, and Honda to help accelerate the development of hydrogen station infrastructure for fuel cell vehicles.

The Japanese government formulated a strategic road map for hydrogen and fuel cells in June of last year, and it has highlighted the importance of developing hydrogen station infrastructure as quickly as possible to popularise FCVs.

Technology

How does a fuel cell work?

A fuel cell uses a chemical reaction involving hydrogen and oxygen to generate electricity.

Each cell only generates a tiny amount of electricity – to generate a usable amount means assembling lots of cells into a stack.

Each cell has an anode and cathode separated by a membrane electrode assembly (MEA) that has the platinum catalyst that breaks apart the proton and electron in the hydrogen.

Hydrogen atoms enter the fuel cell at the anode where they are stripped of their electrons by a chemical reaction – as a result they carry a positive electrical charge.

The electrons, which carry a negative electrical charge, are then available to power an electric motor.

A proton exchange membrane is used to allow the hydrogen protons to pass through to the cathode side.

Oxygen, from the air, enters the fuel cell at the cathode and combines with the hydrogen ions and electrons to form water – the only waste product.

Environment

How friendly?

The operation of a fuel cell vehicle is very clean, producing only water as a by-product. However, there is an issue with the generation of the hydrogen itself.

Many people will have made hydrogen in Chemistry lessons at school – it is just a matter of electrolysing water. However, as an industrial process, this would use a lot of electricity so there is little benefit if you are burning oil or coal to generate the electricity. It only makes sense from an environmental point of view if solar or wind power can be used to generate the electricity.

The main commercial process for generating hydrogen involves “steam reforming” methane from natural gas. This requires the extraction of fossil fuels and the process itself requires heat that – and of course fuel needs to be burned to create the heat. The process also produces carbon dioxide which needs to be disposed of.

Scania has participated in a European project to develop a concept fuel cell bus. Setting out its corporate position on the technology, it said: “Powertrains that comprise a fuel cell and an electric motor could be an interesting alternative.”

However, on the negative side it argued: “A hydrogen fuel cell is reasonably efficient in heavy-duty transport, but no method to transport sufficient amounts of hydrogen gas on a vehicle currently exists. Also, hydrogen must be produced from renewable raw materials, a technology which is not viable at present.”

Applications

Fuel cells for materials handling

In the United States, a company called Plug Power has been supplying fuel cells for materials handling equipment – its GenDrive fuel cells are designed to fit into the existing battery compartment of forklift trucks.

It says it now has some 6,000 of its GenDrive units in use. Customers include Walmart, Sysco, Procter & Gamble, and Mercedes Benz.

Last year, Walmart awarded Plug Power a contract for 1,783 GenDrive fuel cells for forklift fleets at six distribution centres across North America and has since added a seventh site.

Plug Power produces three ranges of fuel cells. The Series 3000 for order pickers and tow tractors are 24V units. The Series 2000 for reach trucks come in 24V, 36V and 48V variants. Plug Power offers the Series 1000 for counterbalanced trucks including 36V and 48V series GenDrive series for 3-wheel and 4-wheel counterbalance trucks.

Power Plug reckons GenDrive products give a 15 per cent reduction in operational expenses. “You’ll gain this benefit through the reduction in man-power, moving more goods, increase in available floor space for storing goods, lower lift truck service costs and reduced electricity usage for battery charging.”

Refuelling takes less than 2 minutes with a Plug Power Hydrogen Fueling System, it says and GenDrive products have an economic life of ten years working in most multiple shift applications.

In the UK, Briggs has been working with Honda on fuel cell powered forklifts.

Plug Power last year started developing hydrogen fuel cell range extenders for FedEx Express electric delivery vans.

The $3 million FedEx project is supported by the US Department of Energy and includes Smith Electric Vehicles as a project partner. The hybrid vehicles use lithium-ion batteries and a 10-kilowatt Plug Power hydrogen fuel cell system. By doubling the vehicle range, which is currently 80 miles, the range extender would make battery-based electric vehicles feasible for nearly all delivery routes.