Friday 15th Dec 2017 - Logistics Manager

Getting to grips with greenhouse gases

Most of the focus of emissions legislation for commercial vehicles has been on pollutants such as NOx and particulates. For example, last year saw the introduction of Euro 6 legislation in Europe – the latest in a series of steps to cut these pollutants.

Malory Davies FCILT, Editor.

Malory Davies FCILT, Editor.

But this legislation does not address greenhouse gases. Trucks can produce any amount of carbon dioxide at the moment.

But that is starting to change. The European Union recently set a target of reducing greenhouse gas emissions by 40 per cent by 2030 (compared to 1990). And, while there is curentlhy no specific target for commercial vehicles, according to the Department for Transport: “In the next few years we expect the European Commission to make proposals for post-2020 new car and new van emission standards. We also expect them to issue a strategy for reducing carbon dioxide emissions from lorries, buses and coaches.”

And action is starting to accelerate in the United States. The US Environmental Protection Agency (EPA) and the Department of Transportation’s National Highway Traffic Safety Administration (NHTSA) have just proposed standards for the period 2021-2027 that would cut CO2 emissions by some one billion tonnes, cut fuel costs by about $170 bn, and reduce oil consumption by up to 1.8 bn barrels over the lifetime of the vehicles sold under the programme.

Politically, of course, it is easier to get people to accept greenhouse gas savings if you can also demonstrate cost savings. And these numbers are big. The proposed reductions are nearly equal to the greenhouse gas emissions associated with energy use by all US residences in one year. The total oil savings under the programme would be greater than a year’s worth of US imports from OPEC.

Medium and heavy duty vehicles currently account for about 20 per cent of greenhouse gas emissions and oil use in the US transport sector, but only comprise about five per cent of vehicles on the road.

The obvious way to cut greenhouse gas emissions is to improve the fuel consumption of vehicles. However, the DOT said the new standards would not mandate the use of specific technologies.

But of course, there is a limit to how far you can cut greenhouse gases from an internal combustion engine. If you burn organic compounds you get carbon dioxide.

And while it is technically possible to turn carbon dioxide into carbon monoxide, which can be made into a fuel, that is currently far too inefficient and expensive to contemplate.

Consequently, the growth in pressure to make internal combustion engines more fuel efficient is just part of the political process – there is unlikely to be any let up in the drive to perfect alternative power sources that enable carbon dioxide to be eliminated completely.