A network of public charging stations for electric vehicles has been installed across Portugal by Oracle and Portuguese not-for-profit company Inteli, as the transport industry gears up for anticipated public enthusiasm for electric cars across the world.

Meanwhile, in the UK, buyers of low carbon vehicles, can get £5000 towards their cost, and trials are proceeding apace on various types of Ultra Low Carbon Vehicles.

But how efficient are they really? Do drivers like them? And will they take off in a big way?

The Portuguese charge up

The Portuguese project, known as MOBI.E, will help Portugal increase its use of renewable energy and become less reliant on fossil fuels. It has seen 1,300 slow charging stations and 50 fast charging stations built as part of the government’s MOBI-E vehicle electrification project.

Portugal already produces 43% of its electricity from renewable sources such as wind and hydropower, so by encouraging drivers to switch to electricity the country will grow even less reliant on fossil fuels and in turn, reduce carbon dioxide emissions.

The country will also host one of Renault-Nissan’s battery plants, which will support the rollout of electric vehicles across Europe.

The MOBI-E platform incorporates Oracle's Customer Care and Billing service, enabling monthly flat rate and time-of-day rating of electricity consumption, network usage and/or additional charging such as parking, roaming between Electric Vehicle (EV) operators and energy retailers.

The power equipment, charging infrastructure and Energy Management Software are all integrated with Oracle software.

“Portugal is leading the charge in making an electric vehicle future a reality,” said Bastian Fischer, Vice President, Oracle Utilities, EMEA. "With motor vehicles being a major contributor to carbon dioxide emissions and with an estimated 800 million motor vehicles on the road worldwide, e-mobility solutions are crucial if we are to meet the European Union’s 20-20-20 targets – to reduce carbon emissions by 20 percent by 2020. We look forward to introducing similar models in other countries."

Charging in the UK

UK advisory group the Low Carbon Vehicle Partnership (LowCVP) predicts there will be a million non-fossil fuel vehicles on UK roads by 2020. This means more vehicles powered by alternative fuels such as biodiesel, biogas, hydrogen, fuel cells, electricity.

Last month, Transport Secretary Philip Hammond launched the Office for Low Emission Vehicles (OLEV) vision for developing the UK’s recharging infrastructure.

The report, ‘Making the Connection: the Plug-In Vehicle Infrastructure Strategy’ maps out the route that Government - as part of its £400m programme to support ultra-low emission vehicles - and industry, will take to support the development of infrastructure that is targeted, convenient and safe.

It's expected that most recharging will be done at home, at night, encouraged by cheap tariffs that use a significant proportion of nuclear and wind power, supplemented by charging at the workplace by commuters and fleets, and ‘a targeted amount of public infrastructure’.

There are now ten vehicles eligible for the Plug-in Car Grant, worth up to £5,000 for buyers of a pure electric or plug-in hybrid car.

Philip Hammond said: “The ability to recharge is a key part of the jigsaw in supporting the growth of the electric vehicle market. It is crucial, therefore, that we make the process as simple as possible.

“Public chargepoints are part of the answer, but putting a chargepoint on every corner is not the right approach. It is most convenient for drivers and best for the energy system for the majority of charging to happen at home.

“Electric cars mean getting out of the mentality of needing to travel to a petrol station and into the habit of refuelling when a vehicle is not being used."

It could mean, then, that in the future there will be fewer petrol stations, and that those remaining will offer a greater variety of fuels and services.

How efficient are they?

A recent trial, run by the motoring organisation RAC - the Future Car Challenge - compared the fuel consumption of three types of vehicle: pure electric; hybrids, including plug-ins and hydrogen fuel cells; and internal combustion engines emitting no more than 110 gCO2/km and found electrics the cheapest to run.

Top came electric vehicles at 0.61MJ/km (megajoules per kilometre), followed by petrol vehicle at 0.91 MJ/km, hybrids, at 1.16 MJ/km, then the only hydrogen fuel cell vehicle at 1.23 MJ/km, and finally diesels at 1.74 MJ/km.

This makes electrics are twice as efficient as the fuel cell vehicle and almost three times more so than diesel.

If you were to translate the performance into miles per gallon (petrol equivalent) the results equate to 147 mpg for electric cars, 83 mpg for hybrids, 65 mpg for diesels, 95 mpg for the sole petrol car and 71 mpg for the hydrogen vehicle.

However, this figure, of course, doesn't take into account the efficiency losses from the point of generation of the electricity to the vehicle's battery, which the vehicle's driver doesn't see.

Looked at from this angle, petrol internal combustion engines used for this particular trial in this location are currently the most efficient, emitting 81 gCO2/km, then hybrids, emitting 103gCO2/km (grams of carbon dioxide per kilometre), closely followed by electric vehicles at 105gCO2/km, then hydrogen fuel cell vehicles with 112 gCO2/km, and lastly diesel internal combustion engines at 147 gCO2/km.

The figures are strongly affected by when charging takes place - there's more low carbon electricity in the mix at night.

They will also vary on a country-by-country basis, depending on the mix of generation.

The drive to develop low carbon vehicles is in anticipation of the future, by around 2020 and beyond, when the proportion of low carbon electricity on the grid will increase as more renewable and/or nuclear power replaces polluting coal and gas powered generation.

But would you want to drive an electric car?

The latest data, from a year long study 25 Mitsubishi i-MiEVs and 20 smart 'fortwo' electric drives, shows that initial scepticism about their capability was overcome by drivers who mainly only use their vehicles for urban transportation.

Most journeys undertaken (77%) lasted less than 20 minutes and only 2% used more than half of the battery's charge. This meant that in most cases a return journey could be made without needing to recharge.

After a while, drivers tended to make longer journeys as they grew more confidence and less worry about running out of charge.

Users didn't feel they had to recharge the battery every time it reached a particular point of depletion. Rather, they be charged it when convenient.

Most of the vehicles were parked for almost all the time - all put 23 hours and 10 min every day on average - so there was plenty of opportunity for them to be plugged in.

Brian Price from Aston University said the data showed that the battery range of electric vehicles more than covers most users’ needs, with most drivers finishing their daily journeys still with over 40% charge remaining. Typical users only need to recharge every 2-3 days and choose the convenience of a home charge overnight or at their place of work over 85% of the time.

Most people started charging when the battery had 81 - 87% of its charge remaining, which matched the fact that most journeys used only around 12% of the batteries charge.

The average charge time was between two and three hours, which costs about the same as a single laundry cycle - 60-80p on a conventional tariff. The smartest participants in the trial used timers to take advantage of off-peak tariffs during the night.

Head of E-Mobility R&D at E.ON Charles Bradshaw-Smith explains: “Meters installed at each user’s home are giving us invaluable information on charging behaviour. The most popular time to charge a vehicle is, rightly, overnight. But as most journeys are relatively short (with five average journeys per charge) this allows scope for exactly when the car is charged each night to minimise cost and maximise carbon savings.

“The ultimate goal is to allow drivers to take advantage of low cost power due to EVs both drawing and feeding into the grid to smooth demand peaks and save carbon."

The data comes from the largest of eight public trials taking part in The Technology Strategy Board’s £25m Ultra Low Carbon Vehicle Demonstrator programme's project CABLED.

Project Leader Neil Butcher from co-ordinating CABLED partner Arup, said: “It’s already clear that EVs offer a viable, practical urban transport solution. We must now consider how our homes, offices and public spaces will need to evolve in order to cater to both users’ needs and the rapidly developing technologies powering these vehicles.”

Mitsubishi Motors’ UK managing director, Lance Bradley is confident these vehicles will catch on quickly: "This clearly backs up our own experience and studies in Japan that people adapt very quickly to driving a pure-EV, such as the Mitsubishi i-MiEV.

"To know that people complete up to five normal journeys per charge, and at such a low cost, underlines the fact that EVs are here to stay and can find mass-market appeal.

“Mitsubishi's new range of plug-in hybrid vehicles and our on-going development of pure-EVs will also help establish electric powertrains in the broader UK market, and go a long way to reducing automotive CO2 emissions."

“Public charging points provided as part of the trial are popular, but less necessary than originally thought," Brian Price added. "The trial has shown that the current generation of low carbon vehicles are as capable as conventional diesel and petrol engines for performance and ease of use, whilst having significantly lower emissions and operating costs.”

However, when you choose to buy a car, you want one that will suit all your purposes - long journeys across country as well as short runs.

Research is underway to develop lead-acid batteries that will charge in much, much shorter times, and to create country-wide networks of charging points.

Until then, unless drivers are confident that they can use one car for all purposes, it's not likely that ELVs will become mainstream.

Motoring organisation the AA recently said, however, that prices of EVs will have to come down before more people will buy them.