Electric Cars: Why Did They Fail ?

Posted on October 16, 2011

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Anybody who says “They havent yet failed – because they havent yet started” only has to check out the short and born-to-fail history of Hydrogen Cars, circa 1998-2005. During that opportunity window for a wonderful new car which would save oil and could save the planet, only badly intentioned and cynical members of the human race could say out loud that Hydrogen Cars were born to fail. Other people, being politically correct or only stupid, said H2 Cars were born to win. But from about 2003 or a bit later the news was out: it was OK and alright to say Hydrogen Cars won’t work. Not only high priced, energy inefficient and overweight, but also downright and extremely dangerous – literal bombs-onwheels made for the Bearded One in a Cave who now reposes at the bottom of the Iranian Gulf, off Oman, by decision of Mr. Obama – who of course loves EVs.

OTHER REASONS HYDROGEN CARS HAD TO FAIL

The simplest question – and exactly 100% the same question for EVs – is where do we get all the electricity for this New Thing ? For H2 Cars it would be needed for producing its hydrogen fuel, throwing at least 30% of the energy away when we are electrolysing water to brew up the hydrogen. Of course the electric car crowd will chip in, here, electric batteries efficiently store electricity and a good motor-and-battery combination will turn well over 90% of the energy supplied from the battery to the motor into mechanical energy for driving the car’s wheels, and the transmission itself can reach 90%+ mechanical efficiency.

The most glaring technical problem with hydrogen cars was the fuel cell, which is a lot simpler piece of machinery then the high-tech name might suggest. The onboard fuel cell was basic and necessary for converting the hydrogen to electricity, to power the electric motor to run the car’s transmission and drive us forward into the H2 Future. But the fuel cell wasted 40% of the hydrogen’s energy converting this energy back to electricity – and electricity was used to produce the hydrogen to run the fuel cell to run the motor to run the drive wheels, if you know the story of the horse which swallowed a spider. That is, hydrogen cars could never be anything but an energy sink, at least 70% inefficient relative to the electrical energy used to make their hydrogen fuel. In practice, with plenty of other little losses, we would normally be looking at an 80% or 85% loss of energy; so why waste time on this transport energy “solution” ? We already have inefficient cars and vehicles running on oil and natural gas or LPG, only throwing away an average of 60% or 65% of their fuel energy – in highway driving mode but wasting more in cities – so why choose even more wasteful transport tech ?

THE DEVIL WE KNOW

What we know about regular thermal-type cars is this: they are cheap and they work. Neither electric cars nor hydrogen cars are cheap, and cannot be cheap. Fuel cells and cryogenic super-cold armour plated hydrogen fuel tanks cost orders of magnitude, even 25 times more than batteries, which themselves cost 100 times more than a cheap metal, plastic or fiberglass fuel tank, when we look at energy storage and supply for a vehicle’s motor or engine. Technical criteria like power conversion rates, energy storage per unit weight for the fuel cell + hydrogen fuel tank, compared with batteries, are already awful. They are simply terrible when we compare either H2 Cars or EVs with diesel, gasoline, LPG or compressed natural gas (CNG) fuelled cars.

Hydrogen tanks and electrical batteries are both very heavy and cost plenty. They both need a lot of cheap electricity “upstream”. We should never forget the upstream energy supply question: How do we produce this electricity ?

As we know, EVs were around an awful long time ago, unlike hydrogen cars. Electric cars and vehicles were quite rapidly “relegated’ to Little League status, for special applications, short-range transport activities and use in environments where no heat, fumes and pollution are permitted. EV fans tell us this proves nothing because all EV problems are being ironed out (and nickel cadmium or lithiumioned out) right now, and everything will soon be fine. Besides, we have windmills to produce “almost free” electricity, and we could tuck a coal-fired or nuclear power plant for back-up discreetly over the horizon, like we do already.

So far and to date, in the real world, EVs still weigh too much and their batteries still cost much too much. One of the early builders of electric cars in the US was William Morrison of Des Moines, Iowa, who began selling them around 1890. Like other pioneers such as Stuart and Edwin Bailey of Amesbury, Massachusetts the electric motors and batteries they fitted to their carriages were too heavy for pulling the carriage, but they kept on trying. By 1908 the Bailey brothers had produced a practical model that could travel about 75 kilometres on flat terrain before its lead-acid battery needed recharging. In Europe, similar activities, including EV development by future big names in thermaltype cars like Daimler-Benz also went ahead. The problem was all these EVs were always too heavy and compared with thermal-type cars were too expensive.

FAST FORWARD

By 1990 things seemed different. General Motors introduced the Impact in January 1990 having a top speed of 110 mph (176 kms per hour), with an experimental version able to hit 290 kmph. It could travel for over 2 hours and cover 193 kms at 88 kms per hour on highways without too many hills and no traffic jams, before needing a 5-hour recharging stop. The more realistic range, as leasors of the car which was not on sale found out, was around 90 – 100 kms before recharging. The Impact, if it had been sold, would have cost perhaps $ 60 000 but the project costing a total of about $1.25 billion for GM was targeted at a 2% slice of the auto market, especially in California, with State legislation demanding that 2% of California’s car fleet becomes “zero emission”. GM began transforming the test car into a production model – but the heavy and expensive battery and its short life were the prime weaknesses, and reasons why GM abruptly stopped the project in 2003, recalled all its EV1’s and Impacts, and destroyed them.

Battery tech had been, and remains high up the list of headaches for GM and all other EV engineers. For the GM Impact project these were originally lead-acid, but engineers also tried other lead-based and Ni-Cd (nickel cadmium) batteries, before moving on to NiMH, nickel metal hydride batteries. Each time there was some cutback in weight for any given power rate and energy storage capacity, but usually at higher cost each time. Battery lifetimes also counted, and still count, with many EVs only able to run if their batteries are replaced every two years, doubling or tripling the vehicle owner’s costs compared to the operating expenses of a gasoline-powered model.

Electric car batteries can be dramatically simple – witness the Tesla Roadster luxury two-seater, which under the right highway conditions and at controlled speeds can run as far as 400 kms on a single charge: the 450-kilogram battery is made up of 6800 cellphone or PC batteries crammed together ! Heat from the battery pack is a major problem, and even a danger, but the battery’s price and therefore the car’s price remain the basic problem for turning Tesla-type cars (about 950 sold for the whole year 2010) from a tiny niche market vehicle, to mass market.

EV batteries have a permanent two-way challenge of cost and weight, made worse by the third killer, security and protection requirements, including battery cooling. Their plastic housings must be sufficiently robust for security needs, but also weigh as little as possible. The batteries contain metal anodes and cathodes in a liquid electrolyte for lead-acid type batteries, but other combinations of fluid and metals are used in higher energy density (up to about 130-140 watthours per kilogram) NiMH batteries, the almost sole possible choice for the electric car horizon. The only other real alternative is low cost traditional lead-acid car power systems, as used by Reva of India.

The bottom line is very simple: Moving any vehicle needs energy, and energy requirements increase as the vehicle’s weight increases. Heavy batteries increase the vehicle’s weight.

ENERGY FOR REAL

The weight and cost problems for EVs is starkly clear from even a quick look at the available and competing battery technologies that currently exist. By no surprise, lithium-ion batteries are the present favourites for EV makers like Renault-Nissan, Chevrolet and BYD, but we can compare any of these battery technologies with regular diesel or gasoline fuel.

One litre of fuel holds or stocks around 10 kWh or 10 000 Watthours of thermal energy which, as we know, is mostly wasted as heat when it is burned inside the engine, converted to mechanical energy, and that mechanical energy is used to drive the transmission system, which turns the car’s wheels. Depending on user behavior, road conditions (stop-start or not), the car’s mechanical condition and other factors, anywhere from 5% to 45% of the fuel energy can be converted to drive energy, with typical average rates around 33%.

Battery Types and Cost 2011 situation

Cost per W-hr capacity W-hr energy per kilogram weight
Lead-acid $0.15 40
Alkaline long-life $0.20 110
Carbon-zinc $0.30 35
NiMH $0.95 95
Ni-Cadmium $1.50 40
Lithium-ion $0.45 125

W-hr: Watthour. 1 kilowatthour (1000 Watthours) of electricity costs around 5 – 25 US cents in most developed countries. 1 litre of diesel fuel contains about 11 kWh, 1 litre of gasoline 10 kWh.

Fuel tanks of most average cars can store 40 litres or more. With a full tank, which took only minutes to fill, the thermal-type conventional car has around 400 – 440 kWh on board even if it is only able to turn about 130 – 150 kWh of that energy into useful drive energy. Taking a figure of 130 000 Watthours, we can find how many kilograms of battery will store the same amount of useful energy (pretending the EV is 100% efficient, not 85%-90%). As you can quickly see, the EV battery would weigh more than 2 tons, if it was lead-acid, and 1350 kilograms if it was NiMH. Then add on the rest of the car.

We did not get on to how much that battery would cost, but you can work it out from the table. Cost and weight are the constant problems for EV batteries – so EV carmakers have cut right back on total energy storage capacity for their batteries, and car weight outside the battery. No present EV except the fantastic priced Tesla Roadster can store more than about 25 – 30 kWh of electricity, equal to the energy content of 2.5 litres of fuel. Vehicle weight is cut to the bone, by tricks like not fitting any spare wheel at all, but using narrow width, self-sealing tyres with ultra-low profiles, cutting seat thicknesses and weight, paring the passenger compartment’s insulation, using plastics anywhere they weigh less than the same component made of metal. On the insulation count, carmakers say that EVs are quiet, so they dont need so much insulation, but this brings up the subject of cold and hot weather: EVs need heating and airconditioning and that costs battery life, cuts the car’s range, and increases the number of times the battery has to be recharged over an average driving lifetime.

A look at where energy losses come from in any car – over and above the weight of the car – shows where EVs gain, and where they face the exact same problems as any thermal-only car. Apart from engine losses and some of the parasitic losses (excluding the aircon and heater systems, wipers, de-icers and related equipment), the EV’s energy losses – drivetrain and power-to-wheel losses – are similar.

BUT WHAT ABOUT THE ELECTRICITY ?

EV boomers invite us to forget the real world. With them, we could imagine that government subsidies to EV buyers are big enough, the prestige value of buying a small family-sized car like a Nissan Leaf for $ 40 000 is high enough, for some kinds of people, and the publicity is so heavy and persuasive that EVs become a mass market hit.

Their energy problem then shifts to even higher gear. Large EV fleets – say anything above 10% of the road fleet – will only, and can only set massive challenges to electric power production, supply and distribution. Every 1 million Nissan Leaf-type or Chevrolet Volt-type cars, each needing around 5 kW to recharge, creates 5000 MW of extra power demand, when or if they all plug in simultaneously. Its nice to hear the “Never mind, we have the wind” chorus from Green Car dreamers, but a high tech offshore windfarm out to sea and out of mind has a capital cost near $7000 per kilowatt, and we need 5 million of those kilowatts, for recharging only 1 million EVs.

The combined car fleets of the USA and Europe count about 440 million units as of 2011. Even symbolic numbers of EVs in the car fleet, let us say 5%, would create massive headaches – and costs – for power producers and distributors, and a swath of problems for power system regulators and managers.

We can put this another way. The world’s present estimated 1.1 billion car and light road vehicle fleet uses about 9 billion barrels of oil a year, nearly 30% of all oil consumption. Shifting that fleet to allelectric by 2040, also assuming the fleet had zero growth, would be just simply impossible. The best approach is to first admit it isnt possible. After that, other solutions can be discussed.

EVs are the no-win non-solution. This is why they failed. QED.

By Andrew McKillop

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