ELECTRIC CONSTRUCTION
batteries in 10 years’ time,”. he says.
‘‘ e European Battery Alliance will
receive over €4billion in EU
funding. Since most battery
technology now comes from Asia,
Europe must close the readiness gap.”
Charging mechanisms must also
be tailored to application. “ e
ECR25 Electric’s on-board charger
plugs into a domestic socket,” says
Nedjimi. “It’s limited by how much
current it pulls from the grid, so it’s
suitable for overnight charging.”
is is ne for doing four hours’
utility work, but not for gruelling
process applications. A one-hour
fast-charger for intensive eight-hour
work means you can recuperate
capacity during lunch.”
Total redesign
Electri cation is more than a
routine power-transplant. Machine
e ciency is key to its feasibility and
every detail must be re-examined to
accrue marginal economies of space
and energy. “Once we had the global
architecture and the energy request,
everything was redesigned,” says
Brehmer. “We redesigned the rear
undercarriage to integrate the
energy and motors. We did huge
work on the turret and analysed
every possible optimisation of
electrohydraulic pilot-controls. We
made the air-conditioning more
e cient with separated batteries and
electrically-driven fans.”
Mecalac is ideally positioned for
this undertaking since it manufactures
most components in-house. “ e
story began when we made our own
swivel-joints to carry hydraulics,
electricity and water,” Brehmer
24 iVTInternational.com November 2019
explains. “High industrial and
technological integration allows us
to redesign each detail.”
e machine must marshal every
ounce and sinew in service of its
power source. But once accomplished,
electri cation’s labour yields abundant
operational dividends and gives
working a whole new feel.
“Obviously there are less fumes,
but also no more vibration in the
cab,” says Nedjimi. “Digging feels
more pleasant and the electric motor
is more responsive. Full power is
instantaneous, and torque is
maintained with no RPM-drop when
you load the engine.” But the e ciency
of electric motors is arguably their
greatest merit. Permanent magnet
motors can achieve 95% e ciency,
compared to 40% at most for
advanced diesel engines.
“We can also use the e12’s
movement for energy recovery and
the instantly-available torque is no
secret,” says Brehmer. But the e12’s
surreal quietness is what strikes him
above all else. “ e silence is
surprising,” he says. “We’re used to
diesel noise, which is about the
engine and the fan. is machine is
working, but you don’t hear it. at
alters your perception totally.”
Reducing ownership cost
Mecalac aims to bring the e12’s total
cost of ownership (TOC) so it is
competitive with diesel counterparts.
“A classical machine’s TCO divides
into thirds,” says Brehmer. “Onethird
purchase price, one-third diesel
energy and one-third maintenance.
Of course, battery costs increase the
purchase-price, but electric energy is
cheaper than diesel, with diesel
prices set to rise 50% in France as
Macron’s administration abolishes
tax-rebates on fuel.”
Electri cation also eliminates at a
stroke the 50% of maintenance costs
which are presently engine-related.
“ e only service consideration is
keeping lithium-ion batteries
charged, ideally above 70%, to
prolong their lifetime,” Nedjimi
cautions. “ e number of cycles
they can carry out in their lifetime
decreases exponentially with depth
of discharge.” Variables di er, but
electric machines essentially repay
a higher initial outlay with lower
running and maintenance costs. “If
€4bn
The EU
funding being
granted to
the European
Battery
Alliance to
enable new
technology
development
ABOVE: Mecalac’s e12
prototype weighs in at just
over 9 tonnes, while Volvo
CE’s ECR25 Electric is a
2.5-tonne machine
/iVTInternational.com