Written evidence submitted by Woodford Owen Consulting Ltd (EVP0056)

This response addresses one aspect of the Call for Evidence:

• “The Government’s ambition to phase out the sale of new diesel heavy goods vehicles, including the scope to use hydrogen as an alternative fuel”.

This response is made by Woodford Owen Consulting Limited, and does not represent the opinion of any other organization including those that employ or have employed the author. While best efforts have been made to ensure that statements are accurate and traceable, no warranty is made to that effect. The author, Nick Owen, has held a CTO / Technical Director role in two technology developers active in the heavy duty sector, and wishes to share his viewpoint on pragmatic solutions to an urgent problem.

Key Points

The key points that I would like to make are as follows:

1. Policy and regulation should always be technology-agnostic as far as possible, as it allows OEMs and solution-providers maximum optionality in meeting society’s needs, considering that products have to be sold in many global markets whose policies may differ from the UK’s but whose environmental needs are ultimately very similar. Some current UK policy is attempting to drive Heavy Duty transport to choose between three solutions (electrified roads, battery-electric and hydrogen fuel cell), none of which meet the full spectrum of the sector’s needs with a suitable degree of robustness / maturity to guarantee a successful solution. With other economies taking a different, more agnostic approach, a re-think is required so that the UK can have a robust policy, and take advantage of global product trends.
2. Policy and regulation should consider greenhouse-gas emissions on a holistic, source-to-wheel or life-cycle basis, as otherwise emissions may simply be re-located beyond the reach of narrower regulation. In particular, tailpipe CO2 is an unsuitable measure for vehicles, causing discrimination against very promising technologies that can meet the sector’s needs and benefit society as a whole. Bio-methane is a prime example, as its tailpipe carbon emissions are fully re-cycled (in fact, by avoiding fugitive methane release to atmosphere, it is carbon-negative), yet those emissions are treated identically to fossil fuel emissions.
3. Energy density of any fuel or energy source stored on the vehicle, is a key consideration in the success of any technology option, and should be recognized as such in policy, both for its impact on reduced payload (which would mean more vehicles to do the same job), and refuelling time (which has implications for both infrastructure and operational efficiency).
4. Speed of Adoption should also be considered as a key factor, given the pressing nature of the “climate emergency”. Any technology that is ready for fast adoption (in terms of its technical maturity and attractive economics to the user), must be part of UK policy, in order to achieve the desired effects in time.
5. The advanced Internal Combustion Engine, or Thermal Propulsion System, has already demonstrated potential to be clean enough that any health effects due to local air pollution are very small compared to other risks to human life. In heavy duty applications, it has also demonstrated efficiency better than that of current fuel cells. Policy should not be hamstrung by the image of older ICE technologies, or scandal resulting from regulatory breaches or inadequacy of regulation. The APC’s Thermal Propulsion roadmap illustrates potential for near-zero air quality emissions, and efficiencies of 60%. These attributes can be achieved using sustainable fuels, including Hydrogen.
6. It should be noted that the UK hosts numerous manufacturers and developers of heavy duty ICE and sustainable fuel technology, including Bennamann, Caterpillar, CNH Industrial, Coryton Special Fuels, Cummins, Delphi, Dolphin N2, JCB, Revolve, Ricardo, and Ulemco, and a strong supporting academic base including Bath, Belfast, Birmingham, Brighton, Imperial College, Loughborough, Oxford, and University College London. Alongside our growing (and important) battery and fuel cell capability, there is an opportunity to nourish and export these ICE and sustainable fuel technologies that is currently poorly supported by UK policy and grant funding.   
7. Policy and regulation should seek to “ban” environmentally harmful fuels (fossil source without carbon capture), and promote sustainable ones, instead of a ban on any device  that converts them to power (internal combustion engine). This could be achieved by altering the way that current fuels are taxed, with taxation applied on the basis of fossil content, and tax free status given to sustainable sources. This principle could be applied to Diesel-like liquid fuels, Natural/Bio gas, Hydrogen or Electricity. As well as creating a “level playing field” to the benefit of the environment, and preventing future scandal over “not so green” fuels, this also would enable the existing vehicle fleet to de-carbonise now.

Some further information on these points is provided below.

Technology agnosticism, and the problem with current proposed solutions

UK policy over the past decade has veered from a successful and world class agnostic approach, toward one of prescribed solutions stemming from policy models. This is dangerous, as it places too much reliance on those models (all of which are no better than their weakest assumption). It allows no flexibility for the industry to find the best solution, nor does it align to the divergent policies of other economies. In particular, many recent UK “policy” publications have suggested that the long-haul truck can only use one of three solutions:

• Electrified roads (catenary), are absolutely dependent on a very costly infrastructure, which would have to cover all trunk roads (not just motorways) in order to be useable. The success of such an infrastructure investment would be without precedent considering the UK alone, but to be useable it would have to align to everywhere that long-haul trucks go – meaning right across Europe and beyond. And the UK has a larger maximum vehicle height, incompatible with the EU’s 4 metre limit. My understanding is that support for this technology in the OEM community is waning; policy-makers should carefully consider the likelihood of international adoption before committing to it.
• Battery Electric is a viable solution for short-haul trucking in any weight class, although it is most cost-effective (and a very good solution) in light to medium vehicles. However, an articulated semi-trailer truck with a range of just 500 miles (considered low for long-haul) requires a battery of around 8 tonnes with today’s technology, which would erode the payload by up to 30% (requiring more trucks to do the same job). High mileages and the need to fast-charge repeatedly could shorten battery life to just 3 years, to the detriment of life-cycle impact. And that fast charging requires around 2 megawatts per vehicle, or potentially 50MW or more in a highway service area. We may get better batteries, but we will never get better laws of physics. Electrification effort is better spent by focusing on where it makes sense (and many in the electrification community will agree with this privately).
• Hydrogen and Fuel Cell is the most palatable of the three options for a long-haul truck. However, today’s fuel cells are no more efficient than a good Diesel engine (this assertion is based on published fuel economy for fuel cell cars in the US; note, it is not the same story as that told in fuel cell roadmaps, where only targets are presented, not measured data). They are also costly, and very vulnerable to small fuel impurities. In contrast, an advanced ICE can better the efficiency of the fuel cell (proven), is very tolerant of impurities (proven), can accept Hythane blends as well as pure Hydrogen (proven), and is able to be manufactured and serviced cheaply using existing infrastructures and skills (which will be readily available as the battery drives the ICE out of passenger cars and buses). A hydrogen-fuelled advanced ICE is a valid option that is unfairly excluded from many grant support schemes, to the detriment of the environment and UK businesses. A more robust policy would leave both options open.

The case for the advanced Thermal Propulsion System             

The case for the advanced ICE or TPS is as follows:

• It exists already in the market and manufacturing infrastructure, therefore uptake of enhanced technology with sustainable fuels can be far more rapid than the deployment of any other solution, creating the required immediate impact on dwindling carbon budgets. As an added bonus, some de-carbonised or sustainable fuels can be used on the existing fleet, either drop-in or with retro-fit adaptation.
• It is already as efficient as fuel cells in the market today, and has demonstrated a viable routemap to greater efficiencies matching those of future PEM fuel cells. The US “Supertruck 2” grant-funded R&D programme has shown several solutions with peak efficiency up to 55%, while advanced concepts with waste energy recovery or split-cycle thermodynamics claim 60%. The so-called “second law” places an upper limit of 75-80% on efficiency, illustrating headroom for development.
• It is capable of clean operation. Multiple studies have shown major benefits of the Euro VI regulation (and its light duty equivalent, Euro 6) on real world air quality; R&D engines have demonstrated NOx levels at a tenth of this, in line with the most stringent Euro VII and California ’27 legislation (SULEV). At this latter level, published data has estimated that human health effects are an order of magnitude lower than road traffic fatalities, or a pandemic every 100 years. Some solutions have even been shown to clean up city air, something that electric solutions cannot do.
• It offers unique optionality on future fuels, thereby creating a greater chance of success than any other solution. Sustainable diesels, bio-ethanols, and bio-methane have all been proven to offer energy density suitable for 1000 miles of onboard range. Hydrogen is less convenient in that respect, but hythanes (a blend of hydrogen and methane) could offer a compromise. All can be used on the same base piston-engine architectures, and all are compatible with future technologies such as lean-burn, waste heat recovery and split-cycle.
• It adds another option in a high-stakes game: Dependency on one of the three high-risk “zero tailpipe” solutions described in the section above, is likely to lead to failure or a slow transition; adding the ICE option increases the chances of addressing long-haul sustainability.

The case for a focus on the Fuel  

In the early days of climate concern, tailpipe CO2 emissions were adopted as a measure of GHG environmental harm. In a bygone era where the only option in use was internal combustion with a fossil fuel, this was a reasonable measure. Today, it is different, and this measure penalizes any vehicle using a sustainable fuel that recycles carbon atoms, while giving a false impression of virtue to any vehicle without a tailpipe at all (electric), or powered by hydrogen. In reality, the emissions created by the production of the “fuel” (which includes electricity) and the vehicle itself, matter equally. Tailpipe zero is not equivalent to Net Zero, and to continue using it as a measure could lead to dangerously undesirable distortion of the market towards technologies whose emissions are out of sight or, worse still, made overseas in less regulated economies. The latter has been described as “climate imperialism”, and could lead to political backlash in future years.

Life cycle analysis is difficult, but this is not a good reason for avoiding it – several manufacturers of electric cars have voluntarily assured that their manufacturing and supply chain are close to Net Zero, because they know that the public understands this issue. An interim step would be to shift away from tailpipe measures, towards measuring the non-sustainable content of fuels.

Fuels considered promising for the heavy duty sector are:

• Sustainable liquid fuels: Ideally formulated as a drop-in so that the whole fleet can benefit. Studies have suggested that the total availability of feed-stocks is insufficient to meet demand; however, with the light duty and heavy short-haul sector poised to shift rapidly to electrification, a greater proportion of heavy duty needs can be met this way. Moving away from Fossil fuels removes the “refinery split” issue, but the availability of bio-ethanol should be considered as a fuel source, not just bio- or synthetic diesels. Sustainable liquids in general offer the best energy density, and some argue that it will therefore be absorbed by aviation. While potentially this is true in the long run, more investment now would create a “transition fuel” that the whole truck fleet can adopt now, until such time as aviation (which uses un-taxed fuel and is therefore more price sensitive) is ready for it – at which time, the fuel is ready to divert to aircraft.
• Bio-methane: Currently overlooked in the UK as it produces (harmlessly recycled) tailpipe CO2 emissions, liquid methane has already been demonstrated to offer 1000-mile range in tanks that fit the critical chassis space of a European-type articulated truck tractor. Natural Gas vehicles are proven and available. Bio-methane can be produced from multiple sources, some (such as sewage and food waste) tapped today, and others (civic and domestic grass clippings and garden waste) not. Adding together such sources can power a significant part of the fleet (claims vary, potentially half of it). An added bonus is that this un-tapped decaying matter releases fugitive methane to the atmosphere. Having 28x the greenhouse potency of CO2, running one truck on this fuel (instead of letting it escape) is like taking ten Diesel trucks off the road – a substantial carbon negative that can assist with climate repair.
• Hydrogen: The most challenging in terms of energy density, but its zero-tailpipe credentials are politically popular, and it is a fuel that the ICE and fuel cell can share, thereby strengthening the infrastructure investment case. It is readily produced from renewables, but also from fossil fuels, which is cheaper, so supply-side regulation or taxation is needed. A further option is to offer the fuel as a blend with bio-methane – so-called Hythane – which offers commonality with a future gas grid (if less so with most fuel cells) and better storage energy density.

References

References on clean, efficient engines (air quality, efficiency, GHGs, life cycle)

1. Finneran, J., Garner, C., Bassett, M., and Hall, J.: A Review of Split-Cycle Engines, In-ternational Journal of Engine Research, (2018), doi:10.1177/1468087418789528.
2. Owen, N., Treccarichi, F., Atkins, A., Selvaraj, A., Barnes, D., Besant, T., and Morgan, R.: A Practical Recuperated Split Cycle Engine for Low Emissions and High Efficiency, SAE ICE2019 conference, SAE Technical Paper 2019-24-0190 (2019).
3. Coney, M., Linnemann, C., Morgan, R., et al.: A Novel Internal Combustion Engine with Simultaneous Injection of Fuel and Pre-Compressed, Pre Heated Air, Proceedings ASME 2002 Fall Technical Conference, September 2002, New Orleans, USA, ICE-Vol. 39, pp. 67-77 (2002).
4. Lam, N., Tuner, M., Tunestal, P., Andersson, A., Lundgren, S. and Johansson, B.: Double Compression Expansion Engine Concepts, SAE International Journal of Engines, Vol. 8, No. 4 (September 2015), pp. 1562-1578
5. Johansson, B. et al: Isobaric Combustion: A Potential Path to High Efficiency, in Combination with the Double Compression Expansion Engine (DCEE) Concept, SAE paper 2019-01-0085.
6. Morgan, R., Lenartowicz, C., Vogiatzaki, K., Harvey, S. et al.,: The Ultra Low Emissions Potential of the Recuperated Split Cycle Combustion System, SAE Technical Paper 2019-24-0189 (2019), doi:10.4271/2019-24-0189.
7. Morgan, R., Khalid, F., Atkins, A. et al: Towards zero emission engines through the adoption of combustion lead engine design realised using a split cycle topology, THIESEL Conference on Thermo- and Fluid Dynamic Processes in Direct Injection Engines (2018).
8. Owen, N., Morgan, R., and Atkins, A.: The Recuperated Split Cycle Engine as a Sustainable Heavy Duty Solution, ATZ Live conference on heavy duty engines, December 2019
9. APC Roadmap 2020: Thermal Propulsion Systems

References on the case for new thinking on sustainable fuels

1. Accelerating Road Transport Decarbonization: A Complementary Approach Using Sustainable and Low Carbon Fuels. Institution of Mechanical Engineers, January 2020.
2. Low Emission Freight & Logistics Trial (LEFT): Key Findings. LowCVP / TRL, November 2020 (Natural Gas vehicles, emissions and range capability).
3. Transport Energy Network: A collaborative approach to understanding decarbonized transport in 2050 - Cross sector energy and propulsion roadmaps, November 2020.

February 2021