Smart-charging that is centrally controlled by a utility does not boost sales of electric vehicles, researchers have found, contrary to earlier predictions, as the cost-savings turn out to be just too small.
Policy makers have long been thinking about how to encourage greater uptake of electric vehicles. Meanwhile, energy companies have been trying to figure out how they might encourage electric vehicle owners to use ‘smart-charging’ systems to recharge their car batteries so as to avoid overloading the grid.
Here’s how some clean transport experts have suggested these two goals could come together: Plug-in electric cars are pretty flexible about when they need to be re-charged. Unlike vacuum cleaners, the electricity they run on isn’t needed immediately. Instead, most people plug them in when they get home ready for use in the morning. But if they aren’t using their vehicles overnight, they don’t all have to be charged at once, which means that in principle, charging could be staggered by some central entity such as the utility we have in British Columbia, BC Hydro.
By shifting the demand (or ‘load’ in energy systems jargon) in this way, to more closely match load with the electricity when it is being produced, smart-charging can help avoid spikes in electricity demand and also potentially be more adaptable to the peaks and troughs of intermittent renewable electricity sources.
Better yet, in principle, by more closely matching demand with supply, smart-charging should reduce how much electricity generating capacity needs to be built out.
The savings realized by not having to build as much energy infrastructure could then be passed on to electric-vehicle owners participating in such smart-charging regimes, in turn encouraging more electric-vehicle purchases by making them cheaper. Previous research into this question had found that smart-charging could offer US$100-300 savings per vehicle per year.
However, up to now, most of these analyses exploring smart-charging have ignored a crucial element: realistic consumer behaviour. Instead, researchers had just assumed that a certain number of electric vehicles would participate in a smart-charging programme.
But that’s not how consumers work in the real world.
So researchers with the Pacific Institute for Climate Solutions Transport Futures team wanted to know what would happen if they incorporated realistic data from a consumer survey of a large number of Canadians into models projecting electricity system models projecting price, capacity and generation, as well as market share of electric vehicles.
Once realistic consumer behaviour was incorporated into electricity system modelling, the researchers found that smart-charging centrally controlled by a utility did not boost sales of electric vehicles, contrary to earlier predictions. This is because it only reduces wholesale electricity prices by 0.6-0.7 percent. This translates into a cost savings per electric vehicle of just $50-70 per year, which is not really meaningful to consumers in terms of reducing the cost of transition to clean vehicles.
Although results will vary in other regions, the modelled behaviour is typical of US and European markets, thus the researchers suspect the findings would hold true in many other regions.
Energy economist Mark Jaccard helped design BC’s carbon tax, and he still supports it. But he questions just how politically viable a stringent tax—at the level needed to meet climate targets—can really be. So he also continues to explore how other policies that the public find more acceptable could work.