Alternative Fuelled Automobiles Study - by Paul Chadwick September 2005

OPEC controls, Asia Oil Demand, Hurricane triggered Oil Shortages & Government Fuel Tax escalators; they all make us think about alternative fuels to oil derived gasoline (petrol) & diesel. Perhaps we should even consider environmentally friendly fuels?

I had the opportunity to try drive some cars powered by different fuels all at one event: DRIVE2005, gaydon motor centre UK September 21st & 22nd 2005.

Here are my experiences and researched-based recommendations:

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Toyota Prius Hybrid Saloon (available today)

A hybrid of petrol engine and electric drive-train. A top quality product and very easy to drive but ultimately flawed by weight and complication. The car positively glides along at slow speeds, weight and smooth electric power makes car parks a silent rolling experience. If you want to take off on the open road then the electric drive supplements the petrol engine and it's surprisingly zippy. It is very dull though on the handling front, the vehicle weight and electric steering gives no feedback or agility. Under the bonnet the cavity is positively rammed with hardware, gas engine on the left, electric motor on the right. Heavy batteries are hidden away under the chassis somewhere. This automatic hybrid vehicle operates seamlessly on the road, ideal for timid drivers who can only use go or stop pedals and who don't care how it does it. This car is fuel efficient, circa 50 mpg but it still uses petrol. In a recent long distance test a modern diesel car was proven to substantially better the Prius's mpg performance. The hybrid nature of this car creates a lot more engineering and cost, service costs for the two power trains could become unaffordable in high mileage examples.

Electric Fuel Cell Powered Car (available circa 2015)

There were none of these to drive. They are still unaffordable test mules in the laboratory. Fuel cells generate electricity from a fuel source (Hydrogen) combined with oxygen from the air to create electricity and water. A very clean technology at the point of use but there are unavoidable challenges with this solution:
1) Hydrogen needs to be supplied in a safe way at the fuel pumps, there's no infrastructure today
2) Hydrogen storage on the vehicle is technical headache, the canister needs withstand high pressures and be kept safe in times of accident (bomb situation)
3) The fuel cells are expensive to manufacture and fragile
4) Fuel cells cannot power the drive motor, think of them as trickle chargers, there has to a be sizable battery buffer to power the car with it's associated weight and servicing costs.
You will probably have to wait until the year 2015 before you can purchase an affordable fuel cell car. The Prius car detailed above is a great test vehicle for the electro-mechanical drive train.

Volvo V70 BiFuel (CNG) (available soon)

This car is designed to run on predominantly Compressed Natural Gas (CNG). This is a popular fuel in Sweden and Germany, where there's already a refueling infrastructure. CNG burns cleaner than petrol or diesel but it's still a non-renewable resource. Natural gas is sourced close to oil reserves using drilling rigs. You can see the silver petrol fuel rail and below four black coloured CNG injection pipes, they have their own supply and injection system separate to the gasoline arrangement. In this car there was only a 5-gallon petrol fuel tank, used exclusively for starting the engine, it automatically switches to gas after starting. You can revert to petrol if you choose, I tried both modes and the car drove identically, same exhaust note, same performance etc. This large car only had a 2.4 litre capacity engine; acceleration was dull whichever fuel you used. You can see from the under boot that the spare wheel has been discarded and replaced by a repair glue canister and air compressor emergency solution. The CNG storage makes a big imposition on storage with a large cylindrical reservoir behind the rear axle and additionally smaller one in front! CNG is compressed at 3000 psi, the oblong cylinders are inefficient spatially when sitting in rectangular boxed spaces. The reduced petrol tank size means that you don't really get an improved driving range by exhausting both tanks sequentially. One interesting opportunity for this solution is the advent of domestic CNG compressors http://www.myphill.com/ . How much does a gallon of CNG cost using British Gas from your domestic cooker? Does the government want to levy a tax on the "new" refilling station in your garage?

Vauxhall Astra petrol car (LPG converted by Millbrook) available today

GM has recently abandoned manufacturing & selling factory built dual fuel cars because of the extra vehicle certification costs compared to the relatively low numbers sold. Millbrook Laboratories converted this Vauxhall very professionally. Liquid Petroleum Gas (LPG) is oil-refined byproduct; as such it's a non-renewable fuel just as petrol or diesel. For the conversion an extra doughnut shaped tank replaces the spare wheel. Emergency tyre repairs are by tyre weld can and compressor reflation. Fuel filler nozzle is carefully located adjacent to the petrol cap in this installation. Under the bonnet a vaporizer converts the liquid to gas and extra injector nozzles are drilled and tapped into the inlet manifold. The car is totally switchable between the two fuels via a dashboard switch. I tried the car on each repeatedly and there was no difference whatsoever although CNG is supposedly poorer in energy. LPG drive range on top of conventional fuel gives admirable driving range. LPG is popular in the Netherlands, France and the UK, there's well established refueling station infrastructure. LPG fuel has a price advantage over petrol but the conversion can cost around 1000gbp, justification is according to your vehicle ownership and personal mileage. LPG is used for domestic heating in areas where mains natural gas not available, this obviously affords a domestic refueling opportunity although I've no idea of the legality, safety or fuel tax implications.

Saab 95 Sportswagon 2.0T (Biofuel- Ethanol) available soon

This ethanol-fuelled car was the most interesting proposal. Ethanol is not new as a fuel, going back to the birth of motoring - the original 1905 Model-T ford was built to run exclusively on the stuff. It's different to petrol in a few subtle ways that affects the technical setup and drive of a car. The car I drove was a German registered left-hand drive car and it had zippy performance from its light pressure turbo-charged engine. The fuel system is versatile and a very affordable option, you simply fill the tank with ethanol or petrol or mixtures of both, there are no separate reservoirs or special start-up routines. Many cars are built with this "flexfuel" ability (FFV), especially in the Americas; it only adds cents to the manufacturing costs. The car I drove had a tank full of a blend called E85 (Ethanol 85% petrol 15%), this is the modern & practical Ethanol blend promoted today. It is very interesting to note that this fuel has a higher octane (near 105 against 97 for regular fuel) the Saab's power output is nearer 180bhp on E85 when compared to 150bhp on petrol, obviously a boon for your racier driver. Under the bonnet the motor had a cam cover citing "ecopower direct injection" this technology involves metered fuel being injected straight into the combustion chamber instead of the inlet manifold (a similar technology to diesels).

BioFuels
These are a hot topic for greener people. They are an exciting alternative to oil because they are totally renewable and carbon neutral. Biodiesel and BioEthanol are produced from crops that are then industrially processed to create high-energy fuels. They are carbon neutral because the crops consume carbon dioxide when they grow the processing and fuel burning release a "equally balanced" CO2 output, they also burn cleaner. Unfortunately it's still cheaper to refine fuels from oil (you don't have all that crop management hassle). There are however interesting challenges to the establishment, Brazil runs all their cars on Ethanol blends, they produce high volumes of the fuel at circa 11pence per litre.

BioFuels Availability
There are special suppliers of biodiesel, vegetable oil based solutions. Bio ethanol is not readily available in the UK, it's also impossible to transport through established petrol pipelines and storage tanks. From 2005 the UK government have subsidized the fuel tax levy on Ethanol by 20 pence per litre to encourage uptake. It's clear that the reliance on oil-derived fuels is a reflection of established distribution infrastructure, Government tax incomes and political lobbying influences rather than a lack of choice of alternatives.

Technical challenges
Methanol is quite corrosive, Ethanol is less so but there are still technical implications for your car, see below for appendix details.

Executive Summary
The popular success of the Toyota Prius hybrid car has galvanized the rest of the motor industry to offer choices with fuel options. Advances motor design, manufacturing and engine management systems have made it affordable to produce versatile cars. Hurricane induced oil shortages and price hikes have raised awareness of oil dependence & global warming issues. There's no better time to convert your vehicle to gas and modify your engine to burn Ethanol. This Tri-fuel versatility will double your driving range, afford you a way to drastically reduce your fuel cost via domestic refueling and adopt environmentally caring fuels as they become available.

 

Ethanol Appendix - further examination of the issues

In your tank
You may not realize it but your car is already burning Ethanol, its added to your petrol blend to improve octane, Pure grain alcohol is rated at 106 octane, and it is so good that it doesn't take all that much to raise the octane of 85 or 87 octane up to 90 octane.

E85 blends
You can imagine that Governments that levy high alcohol taxation don't want people having access to very cheap bulk supplies of pure Ethanol. As a warning, in case you think these alcohols are a cheap way of fuelling your cocktail cabinet, it should be noted that this ethanol is of a dangerously high proof and contains additives (then it is called denatured alcohol), which make it poisonous. Methanol is well known to be a dangerous poison in its own right. The blending of petrol into Ethanol has practical purposes as well; the addition of this relatively small percentage of gasoline overcomes cold-starting issues faced by alcohol and also enhances safety, since 100 percent alcohol burns with an invisible flame.

Reduced Mileage
Gasoline contains 117600 BTU/gallon. Ethanol contains 67000 BTU/gallon. Given those figures you might expect a serious reduction in miles per gallon but in fact it tends to be no more than a ¼ (25%) reduction in MPG and often a lot less. You have to factor this into your price per litre & value for money justification. The higher octane of Ethanol gives you more power, this comes from the Oxygen integral in the chemical formula of the fuel, when supplemented with inducted air you get a bigger bang!

Higher Compression Engines
The Higher octane rating of Ethanol means that your motor can run higher compression (the amount of travel of the piston compressing the air fuel mixture before ignition). Newer cars are designed with higher compression ratios: eg 11:1. This is where ECU controls are really important, when running lower octane fuels they automatically retard the ignition to prevent "knocking" at high compression ratios. Modern car engines design around lean-burn economical technology are generally suitable for ethanol.

Materials - In-Car Fuel systems
There is a lot of confusion here, similar to the switch between leaded petrol and un-leaded. Do you remember the worries about how many cars wouldn't be able to use the new fuel, were you affected? E-85 has not shown to have any significant valve wear problem, if the engine is run normally, but if the engine is not used regularly, there are some corrosion issues in the intake manifold, or in other areas where aluminum or magnesium, or pot metal is exposed to ethanol. Many people mistake Methanol (Wood Alcohol) for Ethanol, Methanol is fairly corrosive. Ethanol will deteriorate natural rubber (rubber swelling issues) but does not seem to hurt the synthetic rubber that's usually used in fuel systems. Another simple way to recalibrate an electronic fuel injected car on e85 is boost the fuel pressure, 10%-increased pressure seems to do it. Metals commonly used in fuel systems are usually ethanol-compatible. Magnesium is known to suffer severe corrosion when in contact with ethanol. Fortunately, it is rarely found in fuel systems. Among non-metals, cork does not fare well with ethanol. Polyurethane and fiberglass-reinforced polyester have also been known to deteriorate in ethanol. Avoid plastic fuel filters - the glasses ones are preferable. Aside from these items, non-metal problems with ethanol are unlikely. Typical automotive fluorocarbon o-rings will swell +100% in ethanol. Rubber gaskets/o-rings/grommets that need to be changed to "Viton" ,which is not affected by E85.

Running regular gasoline car on E85
Given the above warnings you then only have to consider parts of the fuel system and engine that come into contact with unburned Ethanol fuel:
1) Fuel filler pipe
Usually plastic and perhaps susceptible but only exposed during fills
2) Fuel Tank
The motor industry has been promoting plastic tanks for years, cheaper to make more versatile to fit underneath the convoluted shape of the underside of the car. They may be now suggesting a return to metal tanks but it won't be long before they have an ethanol resistant plastic solution.
3) Fuel Pump
Your existing pump will work and may last the life of the car or you may need to change the fuel pump at some stage (2 to 5 years) as the ethanol corrodes the copper used on the bushes of the pump. The ethanol pumps use graphite instead of copper, and silver wires instead of copper wires.
4) Fuel supply lines & Hose
Generally steel zinc plated with plastic inner sheath, probably OK. Rubber hoses need to be of EPDM, most likely anyway
5) Fuel rail
Usually steel zinc plated, no worries
6) Injectors
Plastic moulded with EPDM seals, may be problem - check seals
7) Inlet manifold
Aluminum alloy may be subject to corrosion under long periods of storage but ok in constant use
8) Valve seats
Most engines have harder seats for lean burn and unleaded fuels, should be OK

Fuelling
The lower mpg suggests a higher consumption of Ethanol; the fuel injectors need to squirt a larger measure of fuel into the motor. A suggestion to increase the fuel pressure (above) may work, more fuel squirts into the manifold for a given opening duration of the injector nozzle. A better solution is to make a simple retro-fitting of the Brazilian designed Ethanol conversion - Flextek.

Flextek available from Abcesso for around 100gbp
The idea behind Flextek is that modern, closed loop EFI systems are capable of burning gasoline / ethanol blends of up to 50%. The Flextek wiring harness plugs directly between the injectors and the factory wiring harness. (It's a very simple installation.) The Flextek unit, when running in ethanol mode, modifies the signal to the injectors only, compensating for the burn characteristics of ethanol fuel by changing the injection pulse width. The user must manually select for blends greater than 50% ethanol, all the way up to pure ethanol.

Flextek
A black box ECU is easily plugged in series between your own car's ecu and the Bosch fuel injectors. This very simple "piggyback" device listens to the injector instructions from your original ECU and modifies them for the mixture of Ethanol you are running. It's a 10 -minute job to fit and moveable form car to car. It's a non-intrusive conversion that is revocable.

Bio Ethanol Supplies - create a new domestic industry & save the environment

Brazil leads the world in production & deployment of an Ethanol solution. The make or buy decision is very clouded by political & industrial lobbies. BioMass production needs cultivation space, agricultural efficiency, rainfall and good growing conditions, careful plant species selection, factory process efficiency, co-product & byproduct uses and then efficient fuel distribution. Ethanol is made by fermenting sugar using yeast in water. Just about every farming lobby in the world has "great" ideas about how they can save the world! In the USA they favour corn or wheat, which can be "cracked" into sugar, in Europe we have sugar beet but neither of these come close to the organic productivity and yield density of sugar cane in Brazil. The UK, Japan simply do not have the vast land bank that can be cultivate to produce significant supplies of sugar producing bio-mass. Independent studies have shown that it's not economic to attempt to enter the process chain anywhere in-between (eg buy the sugar and do fermentation alone). It's really important that the co-products and waste products are used properly to create an environmentally sound solution; often there are animal-feed by-product results of the biomass ethanol process.

These comparative efficiency challenges are not stopping local interests forging ahead. Wessex Grain in the UK has outline planning permission to build an Ethanol plant in Somerset.

Further reading:
http://www.e85fuel.com/index.php
http://www.biodieselfillingstations.co.uk/outlets.htm
http://www.envocare.co.uk/ethanol.htm

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