Distribution Grid

What will electric trucks do to the distribution grid?

Tesla recently announced an electric truck. Currently this is a prototype with a target selling price of $200k, which is about 30% higher than a current conventional truck. Although the higher upfront investment may deter smaller operators, Tesla is betting that lower costs per mile will make electric trucks a success story.

However, the real challenge to market acceptance lies in the grid. The truck has a 500 kWh battery. Making the (generous) assumption that ten hours per day can be reserved for charging the truck, that means it needs a 50 kW charger if it uses 500 kWh/day, which Tesla equates to 250 miles driven. So if an operator has ten such trucks, the operator needs half a megawatt of charging capacity. For the whole of the United Kingdom, with about 60,000 HGVs currently registered, this would equate to a peak load of 3 GW just to charge large trucks. It would also mean an annual consumption, assuming 250 miles per truck every working day, of 60,000 x 5 x 50 x 500 kWh = 7.5 TWh/year. So that’s over 4% of the UK’s installed capacity and over 2% of its annual electricity production by today’s measures.

The peak capacity is the big problem. If every owner wants to charge their truck at about the same time of day – and the odds are that many of them will by default – far more capacity will be needed than when a measure of demand controlĀ  is applied. Smoothing the demand completely would halve the peak. So it seems that an important component of a future operating model has to be a fairly coercive demand response based charging plan specifically for truck operators. Failure to do so will mean having to spend twice as much on grid infrastructure, and we will all end up paying for that.