FAQs

Technical

Does it not take more energy to create electricity through fuel cells rather than the alternatives?

While it is true that artificial production of hydrogen requires energy input (i.e. electrolysis, steam reformation) hydrogen can function as an excellent energy carrier. This means that alternative, renewable energy sources such as solar and wind power that have fluctuating power output (i.e. changing wind speed, sunlight conditions) can produce hydrogen to “store” the energy in a form that is usable on demand. Once the hydrogen is stored, energy conversion through fuel cells to create electricity is a spontaneous process that requires no external input to start the reaction (besides the systems to supply fuel and manage the stack).

How does the hydrogen fuel cell work? What does it run on? How do you refill it?

The simple answer is that a fuel cell converts fuel (hydrogen) into energy (electricity). A fuel cell requires only gaseous hydrogen and oxygen to operate, producing water and heat. The hydrogen is stored onboard the vehicle in several tanks, and air is supplied as a source of oxygen. Filling can be done at special filling stations, or from cylinders of hydrogen gas shipped to the garage.

The fuel cell is actually an electrochemical reactor that produces current by oxidizing hydrogen and directing the free electrons across a load (the rest of the electrical systems). Gaseous H₂ is supplied from the tanks, and comes in contact with a platinum catalyst that separates it into single hydrogen atoms. These pass through a membrane that only allows H⁺ ions (protons) through, diverting the electrons through a current collector. These rejoin on the other side of the electrolyte, and combined with oxygen to form water. The reaction is exothermic, so heat is also a byproduct.

What are the costs of the components?

These components are not in mass production (UWAFT is using cutting edge, prototype technology), so they are quite expensive. The cost for the first UWAFT prototype (Challenge X) was in the seven figures range. The current EcoCar will be in the six figures range; an order of magnitude cheaper. Clearly this is an R&D type project that uses “future” technology, but it is technology that is making its way into vehicles even today.

What is the cost of hydrogen compared to gasoline? Isn’t it expensive?

There are two factors to consider when computing the cost of driving a car:

How much does it cost per unit of energy produced (i.e. price per litre of fuel)?
How many units of energy does it take to drive one kilometer (i.e. litres per 100 km)?

In terms of production it depends on how you make the hydrogen. We don’t have hydrogen in its natural state available on Earth, so we make it, commonly through a chemical process called steam-methane reforming that uses natural gas as the feedstock. Electrolysis can also be used (splitting water into hydrogen and oxygen using electricity). One set of estimates pegs the cost of hydrogen at between $0.66 and $0.80 per litre of “gasoline equivalent” (gasoline equivalent means the same energy content as gasoline). Not bad considering hydrogen is not yet produced on the same scale!

Furthermore, one must consider the efficiency of converting that fuel into kilometers driven (i.e. fuel economy). Here hydrogen has a significant advantage, as fuel cell / electric motor powertrains are more efficient than combustion engines (takes less units of fuel energy to drive a given distance). This further lowers the cost per kilometer driven compared to gasoline.

How safe is the vehicle?

The vehicle is very safe. Students are not permitted to modify any safety-related components (i.e. structural members, safety systems, etc.) without engineering analyses that are approved by General Motor engineers. The major components (hydrogen storage system, fuel cell, batteries) are donated by companies like General Motors and A123 Systems, who extensively test their products just as they would an internal combustion engine.

In what state is the hydrogen stored? Liquid, solid or gas? If gas, is it safe?(Doesn’t hydrogen explode?)

The hydrogen is stored onboard as a gas. The tanks are tested to internal pressures far beyond their normal operating conditions, and are crash tested to ensure safety. Hydrogen is highly flammable, and will explode if contained and ignited. However, if the tanks were to rupture the gas would eject and disperse upwards very quickly (hydrogen is significantly lighter than air). This is in contrast to gasoline, which pools and burns underneath the source.

Is the car a hybrid?

Yes, the car is a hybrid. To be specific, our architecture is a “series fuel cell plug-in hybrid electric vehicle”. The fuel cell and battery are the two energy sources, providing power to two electric motors.

What do you do with the old engine that was removed?

There are no plans for the old power plant. Since the donated Saturn VUE uses a special hybrid “two-mode” architecture that was never released, General Motors has to be careful about what happens to it.

How will the car work?

The car is driven by two electric motors, one on the front axle and one on the rear. The vehicle can plug into the electrical grid to charge its batteries. It also carries an on-board fuel cell and hydrogen storage system to generate additional electricity, enhancing range and performance while using a cleaner energy source than gasoline. It is planned to include regenerative braking capability, which basically spins the electric motor(s) backwards to act as a generator, converting momentum into electrical energy to charge the batteries. The vehicle will handle the same as a regular automatic transmission car (in fact there is no transmission in an electric vehicle, so there are no gear shifts at all).

Is the electricity produced by the battery clean?

It depends entirely on where the electricity comes from when you plug in the car; what is technically called the “grid mix”. If all of the grid was supplied by solar or wind then it would be entirely “green” energy. In reality utilities use a mix of coal, natural gas, nuclear, and renewable sources, so electricity is not entirely clean. Compared to using gasoline directly in an engine, however, it is both cleaner and cheaper. As “dirty” electricity generation sources like coal are phased out, this will become even more true.

Why didn’t you put a solar roof on top of the car?

Solar panels do not have the power density required to operate our systems, and can easily be damaged. Solar energy is also unsuitable for this application since it largely depends on the weather and requires direct sunlight to function. Also, despite being a clean method of producing energy, the production of solar panels is actually fairly harmful to the environment.

What are the energy and GHG impacts associated with producing / consuming hydrogen compared to gasoline?

It depends on how the hydrogen is produced. The most popular method right now is a chemical process called steam-methane reforming, using natural gas as the feedstock. EcoCar rules define the well-to-pump or WTP energy use and GHG emissions associated with the production of various fuels (i.e. emissions or energy required per unit of energy supplied to the vehicle, before consumption), for the purposes of scoring the competition. When combined with the pump-to-wheel or PTW (i.e. fuel energy used per kilometer traveled) numbers for the UWAFT vehicle, we get an estimate of the total energy and GHG emissions associated with the production and consumption of a given fuel, per kilometer traveled. These are summarized in the charts below. Notice that there are no PTW emissions associated with the EcoCar (i.e. zero tailpipe emissions). Only emissions associated with upstream production of hydrogen and electricity exist.

Competition

How long is the competition?

The competition spans three years: Year 2 of the challenge began in June 2009 and Year 3 will wrap-up in 2011.

What are other alternative fuels that the competing teams are using?

The teams can use E10 (reformulated gasoline), E85 (ethanol), hydrogen, BD20 (bio-diesel), and electricity. To see what technologies other universities are exploring, please visit the EcoCAR website.

When is the car going to be ready and running/ judged at the competition?

The car must pass a safety inspection performed by competition organizers in March, 2010. This is performed at each team’s garage. Afterwards the vehicle will be shipped to Yuma for the Year 2 competition in May, 2010.

Team

What can I do to help UWAFT?

The UWAFT garage is located between Engineering 3 and Physics at the University of Waterloo. Come by anytime and see what’s happening! We also encourage everyone contact us at questions@uwaft.com.

What program are you from?

Most of the technical team is from mechanical engineering, but we also have students from other programs including chemical and electrical engineering. We also have an outreach team that welcomes students from all faculties.

Where is the garage located?

The main entrance is in the alleyway between RCH and DC, across from E3 at the University of Waterloo. If the garage door is closed (usually shut during the winter), there’s a side door that goes into the back.

Is this done as a class project?

The team is mostly made up of undergraduate volunteers. We do have 4^th year mechanical engineering students doing design project with us every term, as well as a number of Environmental/Business students. Occasionally we hire a co-op student to help out in the garage.

Social

If this technology is so great, what are we (society) waiting for, who cares about cost?

Economics is always a factor in engineering. The infrastructure to support hydrogen or electric refueling needs to be built, and the cost of the technology needs to become competitive with traditional gasoline cars. This transformation is happening right now; municipalities like Vancouver are mandating electric vehicle charging stations and automotive manufacturers are introducing more hybrid and all-electric vehicles in the next few years (most commonly known is the Chevrolet Volt). Remember also that consumer acceptability needs to be maintained (one of the main goals of EcoCar), so things like safety, range, and performance all need to be engineered to match current expectations.