Reducing UK Road Transport CO2

Emissions From Low Carbon Sources

revised 29 July 2010

 

One method of reducing carbon emissions from transport is through replacing petroleum fuelled vehicles with electric ones powered from low carbon energy sources. In this post, we examine how much we would need to increase our nuclear and renewable capacity to meet the UK's transport fleet requirements assuming they are completely electrified and what carbon reduction would be achieved. Any increase in low carbon generating capacity is first allocated to offset the highest carbon generating source which is coal rather than petroleum, so this needs to be part of an overall carbon reduction strategy.

 

The default strategy for this analysis assumes that

 

• 15% of the total electric generating capacity would be required to power road transport, this is consistent with the UK governments low carbon strategy report,
• 15% of total electricity is obtained from wind, similar to that currently achieved in Spain and
• our Nuclear component is increased to 40% of the total.

 

The calculations are tabulated on this spreadsheet using half hourly generating figures for each electric generating source.  At present this only covers three months between March and May 2010, but this will serve as a first approximation. At the bottom of the spreadsheet highlighted in blue are the relative increase in nuclear and wind electric generation relative to current methods, which can be varied by the user. The  total electricity demand, for non transport use is assumed to remain the same than at present.

 

Any excess of power generated from zero carbon sources is first allocated to coal, followed by electric road transport (since this replaces petroleum) and finally natural gas.

 

This overall strategy reduces coal based electricity from 24% to 2%, eliminates the need for petroleum for transport, and reduces the CO2 from electricity generation and transport combined  by 80%.

 

It is assumed for simplicity that the storage capabilities of vehicle batteries and any other balancing systems are capable of utilising any excess of electricity for charging vehicle batteries. This is probably unrealistic without a continental wide grid for renewable electricity, or greater hydro electric storage facilities than we have at present, so it is likely that some additional standby power stations may be required without these systems.

 

There is no allowance in electricity demand due to economic growth, or a reduction in transportation energy measures such COAST or LOCI discussed in the ENTRANS report. These are assumed to cancel out so we can focus on the electrification element only. The indirect emissions from imports are also excluded which is customary in these analysis, but we should remember that climate change is very much a global issue with consumers as well as producers having responsibilities.

 

I have focused here on electricity production for simplicity, however, a significant proportion of carbon emissions in the UK is produced from natural gas for space heating purposes. I will show in a later article how this can be integrated into the energy mix to reduce overall carbon emissions through the strategic design of energy systems in a similar manner to that as described for transport.

 

 

* Having examined the results of more recent trials, I suspect this 15% might be an underestimate.  However, electric battery vehicles are far more efficient and best suited to urban type short distance trips, (which accounts for most of the distance travelled) not higher speed long distance journeys). The latter is best addressed through powering these through fossil fuels until direct electric transmission such as the INITIATE concept, or sustainable 2nd or 3rd generation biofuels become available to fuel one of the techniques described in section 5.4 or 5.5 of the main report .  

 

Environmental Transport Systems

 

Alternative Transportation Solutions through

Integrated Strategies and Technologies