3 considerations for low-carbon vehicle technology

3 considerations for low-carbon vehicle technology

The two primary types of low carbon vehicle that are currently available to the mass market are those powered by electricity (battery electric vehicles, plug-in hybrid vehicles, extended-range electric vehicles) and those powered by hydrogen fuel cells (FCEVs). Battery electric vehicles (BEVs) operate purely on electricity, whereas plug-in hybrids (PHEVs) and extended-range electric vehicles (E-REVs) use internal combustion engines to power the vehicle some of the time. There are several considerations to be taken into account when it comes to each type of technology, the impact on the environment, and the implications for the manufacturer and the end-user. 

 

LCVs and emissions

Although EVs and PHEVs (in electric mode) operate with zero tailpipe emissions, there are some emissions from the source of their electrical power. So until the global infrastructure transitions towards clean electricity, EVs can’t truly be seen as a “zero emission solution”. Despite this, research has found that over their lifetime, EVs in countries such as Sweden and France have average emissions around 70% than ICE vehicles (as their electrical power comes mainly from nuclear and renewables), and in the UK, emissions around 30% lower. Hydrogen fuel cell vehicles (or FCEVs), emit only water and air, so again emit zero carbon from the tailpipe. However, there is a similar challenge – currently, hydrogen fuel is produced and transported to pumps using fossil fuels, but as demand rises and investment in the technology increases, the infrastructure will be able to develop and we will be able to reduce emissions in the supply chain. 

 

Energy density 

Ostensibly, a major concern in consumer vehicles is their range. Manufacturers working on LCV projects are continually trying to find ways to extend the range of alternative fuel vehicles. Currently, the BEV with the longest range is the Tesla Model 3, which has a 405-mile range on one charge (although this is currently only an estimate), which is longer than the average for ICE vehicles, with most having a 250-300 mile range. PHEVs and E-REVs can match or exceed the range of an ICE vehicle, but only a part of this range is powered purely by electricity. E-REVs have a range of around 150 miles after which the onboard ICE generator kicks in to charge it. PHEV batteries usually have a range of around 20-30 miles. BEVs are able to achieve increasingly longer ranges because of the high energy density of the large lithium-ion battery packs that are used within them (around 100-265 Wh/kg). 

Hydrogen fuel cells vehicles can achieve ranges of around 300 miles to match the average of current consumer vehicles, however, this comes with an additional challenge. Hydrogen’s energy density is significantly lower than that of both li-ion batteries and gasoline, at around 8 mJ/L. To meet the current standards and range of consumer vehicles, a significant amount of hydrogen would need to be stored on-board, with tank capacities for around 5-13 kg of hydrogen. While the hydrogen storage weighs less than li-ion delivering the same amount of range, the concern is the volume of these tanks and the space that they would need to take up. Therefore, thus far it’s been proposed that hydrogen fuel is primarily a solution suitable for larger vehicles, not necessarily passenger vehicles. 

 

Energy efficiency

Of course, when it comes to powering a vehicle, it’s not just about how much energy you can store, it’s about what you can do with it. A study by Volkswagen found that the energy efficiency losses suffered by hydrogen from “well-to-tank” (from production to use within the vehicle) are significantly higher than those suffered by li-ion batteries. The overall efficiency rate of electric vehicles is around 76%, compared to hydrogen, which is 30%. This is due to all the ways in which the hydrogen has to be processed in order for it to power a vehicle – from generating the energy, it goes through electrolysis, then compression and liquefaction, then transportation and filling, then into the fuel cell, then into a low capacity battery, then into the engine. By contrast, electrical energy is generated, transported and stored, transferred into a high capacity battery then into the engine.

 

Elmelin are working closely with automotive manufacturers to develop innovative insulation solutions that will help them to address challenges with safety, performance and efficiency in battery and fuel-cell electric vehicles. If you’d like to find out more about our solutions, get in touch

The pros and cons of hydrogen fuel cells

The pros and cons of hydrogen fuel cells

Despite a 5.8% drop in global carbon emissions in 2020 due to the COVID-19 pandemic, emissions are still at critical levels. Global CO2 emissions were 31.5Gt – an increase of 54% since 1990.

With that in mind, the quest to find a viable alternative to carbon-based fuel and energy production processes is continually accelerating. From passenger vehicles to domestic energy, those at the forefront of alternative fuel and energy storage technology are exploring options.

One of these options is hydrogen fuel cells – an efficient energy source with low emissions. In this article, we’re looking at the pros and cons of the widespread use of hydrogen fuel cells.

 

Pro: Low emissions and higher efficiency

Hydrogen fuel cells work by combining hydrogen and oxygen to produce electrical energy. The only emissions that result from this process are water (H20) and hot air – meaning that no harmful gases are released into the atmosphere, in contrast to the 4.6 metric tons of carbon dioxide a typical passenger vehicle emits each year. In addition, hydrogen fuel is more efficient – internal combustion engine (ICE) vehicles convert fuel into kinetic energy at 25% efficiency. Hydrogen fuel cells do so at 60% efficiency.

 

Pro: Relatively low barrier to entry

Fuel cell electric vehicles (FCEVs) have low barriers to entry in terms of societal change.

They operate and perform very similarly to the conventional ICE vehicles we are used to, allowing you to refuel at a station within minutes, as opposed to having to wait for an electric vehicle (EV) to charge. An electric vehicle typically has a range of around 230 miles, whereas FCEVs can reach 310-370 miles range without having to be refuelled. In addition, an EV can take up to 8 hours to charge from empty to full – it takes roughly 5 minutes to refuel a hydrogen tank.

 

Potential challenge: Storage

High-density hydrogen storage is a challenge for both portable and stationary applications. The storage solutions we have available currently typically require the storage of large volumes of hydrogen in gaseous form. To reach the performance and efficiency goals for light-duty FCEVs, large-volume, high-pressure compressed gas tanks would need to be used, which can have a significant footprint.

 

Pro: Effective in stationary and heavy-duty applications

While this is a challenge for “light-duty” FCEVs, it is less so for larger, heavy-duty vehicles and stationary applications, where the footprint of the gas tank is less of an issue. Bulkier vehicles that need to travel long distances, carry heavy loads and refuel with minimal downtime are good candidates. For that reason, hydrogen fuel has been tested in vehicles such as trucks, boats, trains and planes.

In addition, hydrogen could also be used to replace the compressed natural gas used in some domestic applications. A study by Swansea University found that up to 30% of domestic gas could be safely replaced with hydrogen without requiring changes to boilers or ovens.

 

Con: Less efficient than batteries

When comparing hydrogen fuel cells to other potential alternatives to hydrocarbon power, the picture becomes slightly less positive. The viability of FCEVs is being threatened by the continued development of more cost-effective battery technology and lowering costs of electricity-based transport systems. EV and hybrid vehicles overall offer better efficiency than FCEVs. Electric batteries lose only 17% of their initial input of energy through inefficiencies when charging and discharging. The cycle used to create electrical energy within a hydrogen fuel cell wastes more than 50% of its energy efficiency.

 

Hydrogen fuel cells and insulation

Just like batteries, hydrogen fuel cells produce electrical energy, and present their own unique safety and efficiency challenges – so there needs to be careful consideration in how the cells are insulated.

We’re committing ourselves to help our customers contribute towards the net-zero initiative. We’re currently working on a number of projects and solutions which will help to increase the safety, efficiency and cost-effectiveness of alternative fuel. If you’d like to find out more about our solutions, get in touch.