This is the second part of a series of articles that will hopefully develop a debate on the best and most cost-effective options available to fleets and air quality managers to enable compliance with air quality standards in relation to NOx (or NO2) levels. Read Part One, here.
The question on the table is â€˜How long until the future arrives?â€™ Much is heralded about new technologies to produce fuels that will be both carbon neutral and clean with regards to air quality pollutants. However, no-one really explains the nuances behind these options and what will be required to deliver them. So, letâ€™s try to unpack some of the issues that need addressing. We donâ€™t have all the answers but if we know the right questions then at least we go into the future with our eyes open.
Letâ€™s start with near to market technologies that are gaining momentum. Current hybrid technology is seen mainly in cars as an add-on to the existing engine. Depending on the size of batteries in the vehicle then that determines the â€˜zeroâ€™ emission range. Fine in theory, but look at the additional weight you are carrying compared to the standard version of that vehicle and there is a hidden factor. We all know carrying extra weight saps fuel economy, enough said. Add to that the use of lights, wipers, heater, and â€˜Zeroâ€™ emission range is affected (the same goes for electric only vehicles â€“ but at least the electric van suppliers are now being clear about that effect with potential customers). I personally ran a diesel hybrid car that was supposed to do 75mpg but no matter how I drove it I couldnâ€™t get beyond 50mpg. Sadly, the standard diesel would do over 50mpg, which offers little payback on the increased purchase price.
The weight of the vehicles is an easy give away and a highly important factor for commercial vehicle operators (vans, buses, and trucks). Letâ€™s have a quick look at the Nissan NV200 series. The standard van has a GVW of 2000kg, a base weight of 1272kg and payload of 728kg, the ENV200 however is plated at 2220kg with a base weight of 1542kg and payload of 678kg: over 20% heavier in base weight.
Where is all the copper and lithium going to come from for mass market adoption? No surprise that the price of copper has risen by some 50% since 1990 with lithium rising by over four times its price in 2000, standing at over $9,000 per tonne today. With limited global supplies, there are much needed developments in other battery types.
Fuel cell vehicles reveal more about the weight penaltyâ€¦a Toyota Mirai weighs in at 1850kg compared to a Toyota Prius Plug In at 1420kg (and a Auris at 1300kg). The very large hydrogen tanks alone weigh 88kg with 5 kg of hydrogen capacity. We therefore have some weigh (sic) to go until performance isnâ€™t affected by the additional weight.
Then there is the issue of where the hydrogen comes from. Most hydrogen used in the UK is derived from steam reforming natural gas which takes energy. This means that whilst the hydrogen is cheaper than renewable hydrogen (from electrolysis) at around Â£6/kg (c.f. Â£10/kg ReH2) it has a higher carbon emissions (circa 28% increase) than diesel fuel on an energy equivalence basis! We will go into real life pence per mile costs in the next article.
Donâ€™t get me wrong, these technologies will have a role to play in certain drive cycles or specific operations but if you are a cash-strapped council what will your choice be?
Much is being said about the use of gasification or pyrolysis as a means of â€˜breakingâ€™ down waste to produce a synthetic crude oil or a synthetic gas that can then be â€˜daisy chainedâ€™ through a Fischer Tropsch route to produce synthetic petrol, diesel, or aviation fuel. There are some welcome pilot facilities being built in the UK to test these processes and we wait with baited breath on the resultant cost of the fuels produced and the scalability of the production. We need a holistic approach that also looks at the Air Pollutant effects from all these different processes.
The thing that concerns me, is that as I travel around the UK I see increasingly more Waste to Energy (incinerators to the lay person) plants operating or being built. These have 25-year feedstock agreements with various councils or waste collection companies. Hence the timing for the commercialisation of these new process developments will be key to their success or not. The organic element of these W2E feedstocks is fundamental to their combustion processes so where will the organic feedstocks come from for the gasification or pyrolysis processes? Everyone will be fighting for the same feedstock which will result in an increased cost of said feedstock no doubt.
If councils are wise, then the value of these feedstocks will be recognised and utilised in negotiating the deals in the first place, which could result in the supply of discounted energy to the council facilities.
In terms of vehicles, I am monitoring with great interest the range extender (RE) platforms as I believe they will provide a cost-effective solution for the next 30 years. The Mitsubishi Outlander PHEV is the first of this new breed where the engine predominantly acts as an on-board electricity generator and so can be optimised in its performance. The Metrocab range extender London taxi that has a 1litre petrol engine acting as the generator to give full useable range through on-board recharging (as well as plug in capability when available). It will deliver economy and significantly reduced air pollutant, but at a price. When you look at this same technology for a van or a rigid truck, covering higher mileages and using GPS to ring fence running in electric only mode in certain locations, then we start to see how we can improve upon and move away from the traditional diesel engine currently in use. Make the RE engine run on BioLPG or Biomethane and you have a very cost effective option in front of you.
We cannot get away from the fact that we are in a global economy. We need to be mindful of developments elsewhere and how we can engage with these global developments so we donâ€™t try to re-invent the wheel. For all these aspects, we need to consider if what the answer will be for the next 5 years as well as for 2030 or 2050. And depending on that answer, we will need to help fleet operators develop a cohesive plan that ensures they have the most appropriate vehicle to do the job, in the most cost effective way, surely?
This article has been contributed to AirQualityNews.com by emissions consultant JouleVert.