* French grid already sensitive to demand spikes
* Smart grids and smart chargers seen as vital
* Controlled expansion could rebalance networks
By Michel Rose
PARIS, March 26 France's power grid, already
under strain at peak periods, could struggle to cope if growing
numbers of electric car owners all recharge their batteries when
they sit down for dinner, power sector executives say.
Renault launched its long-awaited electric car Zoe
in France this month at a price on a par with petrol peers,
making it the first electric vehicle with mass-market potential.
The government, meanwhile, has been encouraging the technology
with generous subsidies.
But this comes in a country with a power grid that is
already extremely sensitive to spikes in demand because of its
high reliance on electric heating.
Though the prospect of a fleet of hundreds of thousands of
electric cars remains some distance off, France needs to
consider how it will cope when cold winter evenings prompt
households to turn on the heaters, lights and electric gadgets
at the same time.
"If it's badly managed, it could prompt power surges, which
would cost a lot in peak production, CO2 emissions and would
also necessitate the construction of relatively costly
infrastructure," Olivier Grabette, head of R&D at French power
grid RTE, told Reuters.
Grabette said that under the "ambitious" scenario of a fleet
of two million electric vehicles by 2020, total French annual
electricity consumption would rise by 1 to 3 percent.
"It's not huge in terms of energy," Grabette said. "But if
all these vehicles charge at peak times, even with slow car
chargers, it could add between 3 and 6 gigawatts (GW) of peak
demand, which would be felt if it comes at the wrong moment."
Data last year from U.S. eco-town Mueller, in Texas, showed
that owners of electric cars typically plugged in their vehicles
when home electricity use spiked, causing potential problems for
the grid. (r.reuters.com/zun86t)
The heavy reliance on electrical heating in France was
instigated by successive governments to absorb surplus nuclear
power. Its 19 nuclear power plants make France Europe's biggest
electricity exporter and ensure generally steady power supplies.
However, it lacks flexible capacity - usually generated by
gas, coal or oil-fired plants - to meet peak evening demand
during cold snaps.
Peak demand has hit record highs in each of the past 10
winters. In February last year demand at one point hit more than
102 GW and pushed the network to its limits, obliging France to
import a record 9 GW.
RTE and other state agencies identified the problem in a
2011 report and recommended car chargers that take up to eight
hours to recharge a vehicle. Though quick chargers do the job in
about 30 minutes, these draw more energy than a dozen electric
There is also the problem of a geographical concentration of
cars drawing power from quick chargers; at supermarkets,
motorway service stations or business districts, for instance.
"The issue is not the total number of vehicles, it's how
they will spread - and we think they will spread in clusters,"
said Laurent Schmitt, Smart Grid Vice-President at French
engineering company Alstom.
"You can have only 1,000 cars, (but) if 500 of these are
connected to the same building, you'll have a problem with this
building and the neighbourhood around it," he said.
The key could be off-peak charging via "smart grids" able to
communicate with chargers that can then be operated remotely.
"There could be a problem, if we're not careful, in terms of
peak capacity," said Bruno Dobrowolski, in charge of the
electric vehicle programme at ErDF, the electric distribution
arm of state-owned utility EDF. "That's why smart
charging is necessary."
French Industry Minister Arnaud Montebourg, the first
Renault client to be handed the keys of a Zoe, has appointed a
committee to advise on the expansion of the charger network.
Renault's decision not to provide chargers compatible with
home sockets, thereby requiring Zoe owners to buy "Wall-Box"
chargers, could soften the impact. In Britain, Renault will
subsidise the cost when the car is launched there in June.
The partly state-owned carmaker says owners could also use
smartphone apps to set charging times depending on power prices.
"If it is developed well, in a coordinated way, it isn't a
problem and could even help to rebalance a network, especially
by integrating more renewable energy," RTE's Grabette said.
Electric cars' batteries could smooth the variability of
wind and solar energy by storing wind power produced at night
and injecting it back to the grid when it needs help, he said.
Such vehicle-to-grid systems are already being tested in the
United States and Japan.
Alstom's Schmitt said France has domestic industrial players
in each of the necessary fields of expertise, but the government
needs a strong hand to ensure an integrated approach.
"You don't need to work with 10,000 players, but five or 10
who are leaders in their field. However, that raises the issue
of the big players' egos," Schmitt said.
($1 = 0.7694 euros)
(Editing by David Goodman)