If you think that the moment you get into an electric vehicle you have left the world of carbon emissions behind, then you might want to think again. While electric vehicles do not emit carbon themselves, they all sit at the end of an energy chain that begins with someone, somewhere, generating electricity; electricity that may or may not be emissions-free.
Finding green electricity
In a worst-case scenario that electricity may even produce exceptionally high emissions – for example, a coal-fired power station not only pours CO2 into the atmosphere, but also sulphur dioxide, nitrogen oxide, arsenic, lead and mercury.
But let's not be pessimistic. We know an electric car does not generate its own emissions and we also know that in a perfect world it could use 100 per cent green electricity. The question then is where do you find that green energy and how can you be sure it is as green as it claims to be? That's essential information – without it the green automotive proposition starts to unravel.
On a global basis the proportion of electricity from green renewable sources is still low. In the European Union it makes up 33 per cent of electricity consumed, while in the US it is just 11 per cent. But figures vary widely country by country: Denmark, for example, produces 46 per cent of its electricity from wind energy, with biofuels and solar on top.
Generate your own
So is there any way you can guarantee that the electricity you feed into your car is truly green? The answer is yes, although it is not as easy as you might hope.
One thing you cannot do is separate out green electricity from the non-green variety once that power is fed into the national grid. Electrons are just electrons, and they don't carry any information as to where they have come from or how they were generated.
Private power grids are different. If you have your own renewable generator – and some people do, usually in the shape of a solar panel array – then you can charge your car at home and join the select world of the 100 per cent green motorist.
If you have to buy power on the open market, then your next best choice is a green energy supplier. And that is where the complications begin.
Check your supplier
In the UK for example there are numerous suppliers selling “green electricity” but this isn't always as straightforward as it seems.
Some companies don't generate any electricity themselves and just trade certificates. They buy electricity on the wholesale market, then also buy perfectly genuine Renewable Energy Guarantee of Origin certificates or “REGOs” that allow them to label any electricity they are selling – whatever the source – as green.
If you think this sounds slightly questionable then you are not alone. A recent survey in the UK found that one-third of all consumers believed that if they bought electricity on a “green” tariff then they were using 100 per cent renewable energy, which is not the case.
Other companies buy green energy from green power generators and sell this – but the challenge here is that they aren't building new sources of green, renewable energy to boost the total amount of green energy available.
Time to step up
There are electricity suppliers that do generate all of their own power and from 100 per cent renewable sources. Although there aren't many – fewer than five out of a total of about 60 suppliers in the UK, for example.
Maybe it is time for all these power generators to get their act together and start delivering the kind of renewable power that consumers want them to deliver. Because if they don't, the ever-increasing number of electric vehicle users are going to notice that “zero emissions” doesn't always mean zero emissions. And that could put the brakes on the green mobility revolution that all of us are hoping to see.