RV FEATURE
such that it makes no sense to continue
to use such vehicles. Some countries (such
as Norway) offer major financial incentives
to change.
The only realistic alternative power is electrical.
A petrol engine is about 25% efficient (i.e.,
75% is lost mainly as heat), but an electric
motor is 80 to 90% efficient (heat loss is a mere
10-20%). A huge benefit of electric motors for
caravan towing is that electric traction motors
develop maximum (and considerable) torque
when most needed – at zero and low rpm –
enough for restarting on an ultra-steep hill, or
moving with ease in deep sand.
A current downside is that almost all of
Australia’s grid energy is obtained by burning
fossil fuel in far-from-clean power stations. It
hence makes no sense to use an electric-only
car – unless that electricity is generated from
solar. Here, the electricity industry is at odds
with government policy – the industry seeks
to use solar, tidal and wind power.
While not many do so, some, who (like myself)
have 6kW-plus home solar, run small electric
cars from their excess energy. This can be done
at night if necessary, by selling excess solar
power to an amiable grid supplier and buying it
back again at low, agreed off-peak rates at night.
THE IDEAL RIGHT NOW
Right now, the ideal tow vehicle is a hybrid 4WD.
This is because a hybrid generates less pollution
than an electric-only car run from Australia’s
current grid power. This must inevitably change
but the situation is currently driven by politics
rather than valid technology.
Eventually, as our grid power is progressively
produced from non-fossil sources, and
automotive electric charging stations are at least
as common as our current petrol stations, hybrids
will progressively be phased out. This is likely to
happen in Australia by 2030. In Norway it already
has.
BENEFITS FOR TOWING
Unless there is a truly major change in battery
technology (unlikely) that would enable lighter
and more energy-compact batteries, electric
vehicles suitable for towing caravans are likely to
be some 400kg heavier.
Providing existing caravan weight classifications
remain unchanged, this additional weight is a
major safety benefit for on-road caravans. It
is likely to result in tow vehicles outweighing
caravans. It will not adversely affect offroad tow
vehicles as their tyres will be correspondingly
larger.
One major change may need to be to a
secondary source of electrical energy for RV
domestic use. This may well be the fuel cell
that at last appears to be other than limited
to the Efoy products that use methanol to
generate 12 volts DC.
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