electrified road Sweden Guardian 2018-04 12
https://www.theguardian.com/environment/2018/apr/12/worlds-first-electrified-road-for-charging-vehicles-opens-in-sweden
World's first electrified road for charging vehicles opens in Sweden
Stretch of road outside Stockholm transfers energy from two tracks of
rail in the road, recharging the batteries of electric cars and trucks
The world's first electrified road that recharges the batteries of cars
and trucks driving on it has been opened in Sweden.
About 2km (1.2 miles) of electric rail has been embedded in a public road
near Stockholm, but the government's roads agency has already drafted a
national map for future expansion.
Sweden's target of achieving independence from fossil fuel by 2030
requires a 70% reduction in the transport sector.
The technology behind the electrification of the road linking Stockholm
Arlanda airport to a logistics site outside the capital city aims to
solve the thorny problems of keeping electric vehicles charged, and the
manufacture of their batteries affordable.
Energy is transferred from two tracks of rail in the road via a movable
arm attached to the bottom of a vehicle. The design is not dissimilar to
that of a Scalextric track, although should the vehicle overtake, the arm
is automatically disconnected.
The electrified road is divided into 50m sections, with an individual
section powered only when a vehicle is above it.
When a vehicle stops, the current is disconnected. The system is able to
calculate the vehicle's energy consumption, which enables electricity
costs to be debited per vehicle and user.
The "dynamic charging" - as opposed to the use of roadside charging posts
- means the vehicle's batteries can be smaller, along with their
manufacturing costs.
A former diesel-fuelled truck owned by the logistics firm, PostNord, is
the first to use the road.
Hans Säll, chief executive of the eRoadArlanda consortium behind the
project, said both current vehicles and roadways could be adapted to take
advantage of the technology.
In Sweden there are roughly half a million kilometres of roadway, of
which 20,000km are highways, Säll said.
"If we electrify 20,000km of highways that will definitely be be enough,"
he added. "The distance between two highways is never more than 45km and
electric cars can already travel that distance without needing to be
recharged. Some believe it would be enough to electrify 5,000km." At a
cost of 1m per kilometre, the cost of electrification is said to be 50
times lower than that required to construct an urban tram line.
Säll said: "There is no electricity on the surface. There are two tracks,
just like an outlet in the wall. Five or six centimetres down is where
the electricity is. But if you flood the road with salt water then we
have found that the electricity level at the surface is just one volt.
You could walk on it barefoot."
National grids are increasingly moving away from coal and oil and battery
storage is seen as crucial to a changing the source of the energy used in
transportation.
The Swedish government, represented by a minister at the formal
inauguration of the electrified road on Wednesday, is in talks with
Berlin about a future network. In 2016, a 2km stretch of motorway in
Sweden was adapted with similar technology but through overhead power
lines at lorry level, making it unusable for electric cars.