Monday , September 28 2020
Home / Energy / How will we get around in a future without petroleum?
Hydrogen Bus

How will we get around in a future without petroleum?

This may seem a frivolous question given that there is more oil beneath the ground than humans have burned in the last century.  But it is not so frivolous when we consider the impact that petroleum has on the environment.  If governments are going to meet climate change targets, sooner or later we are going to see limitations on petrol and diesel vehicles.  Most likely, this will be done through taxation; effectively driving up the cost of travel.  We face a similar problem with future oil production, because we have run out of cheap (to produce) oil.  To recoup the greater investment costs of extracting oil from the Arctic, deep water, tar sands and shale, the price of petrol and diesel are going to rise for end users.

Faced with this prospect, the early adopters are already buying electric and hybrid vehicles.  But this brings us back to a question that has been raging for more than a decade – electric or hydrogen?

The Elon Musk/Tesla model can be summarised as “electric business as usual”.  We all get to carry on running millions of private electric-powered cars using a new infrastructure of fast charging stations to recharge the hi-tech batteries.  Aberdeen – Scotland’s oil capital – is the latest city to offer an alternative approach in which more efficient mass transit takes the place of private vehicle use.  In the Aberdeen scheme, a fleet of hydrogen buses have replaced the old diesel buses to provide clean transport around the city.

Both models have their problems.  Electric vehicles are only cleaner than petroleum ones if the electricity they use is generated from renewables.  If not, they are merely transferring the pollution to the power stations.  At present, the Aberdeen vehicles use wind-powered electrolysis to generate and compress the hydrogen that fuels the 10 hydrogen buses.  However, as with battery storage, electrolysis has negative net energy – you put a lot more energy in than you get back.  If larger volumes of hydrogen were needed – for example, if every large UK city followed Aberdeen’s lead – it would have to be separated out of natural gas… a process that releases carbon dioxide into the atmosphere.

In practice, electric and hydrogen transport is only green when it is small scale (and this ignores the fossil fuels that go into manufacturing the vehicles and their infrastructure).  Once you imagine all of the cars, vans, lorries and buses on our roads every day switching over to electricity – which is still generated largely from coal, gas and nuclear – you realise that it cannot be done at scale.

The strength of the Aberdeen model (and weakness of Musk) is that it at least acknowledges that private motoring in a world of expensive petroleum and stricter climate targets is simply not going to happen.  Electricity generation – which currently accounts for just 20 percent of our energy consumption – would have to expand massively if a large part of the 40 percent of our energy consumption that currently powers our transport were to switch to the Grid.  While a few thousand early adopters might get away with it, there is simply no possibility that several million of us are going to be using our creaky National Grid to power our electric vehicles any time soon.

It is this realisation that causes most of us to mentally switch off, and pretend that in a future in which energy is expensive, we will still be doing all the things that we did when energy was cheap.  People are still buying large, gas-guzzling SUVs on the strength of the temporary fall in oil prices.  Governments are still committing to massive road infrastructure projects in a manner that would only make sense if someone had discovered a massive new reserve of magic petroleum that doesn’t produce carbon dioxide when it is burned.  The reality, of course, is that all of the cheap easy oil has gone.  What is left is the opposite of what is needed – it is expensive and it is dirty.

What the Aberdeen model offers is part of the answer to the question nobody wants to answer: How will we get around in a (near) future without petroleum?  The answer is that, for the most part, we won’t.  The 75 percent of journeys that are less than a mile are going to be done on foot, on bicycles or on local mass transit systems.  Longer journeys will be far less frequent, and are going to be in buses and trains not (for most of us) private vehicles.  And if we can build an energy infrastructure that will allow a large part of the buses, trams and trains that we are going to need to run on renewable energy systems, so much the better.

Check Also

A brown new deal

Those lucky enough to die of old age often fall into a very peaceful state …