RV FEATURE
MYTH
5
OUR GENERATOR’S OUTPUT
IS AS CLEAN AS GRID POWER
This claim is true of high quality inverter-
generators, but not necessarily of others.
If powered (as many cheap ones are) by a single-
cylinder engine, the piston in that engine is, on
each stroke, changing rapidly in velocity as it
compresses, burns via rapid expansion, and then
slows on the exhaust stroke.
For the big units, where weight is no object, this
can be damped via a heavy flywheel. But for
smaller ones, the result is the desired 50 or (in the
US) 60 cycles a second overlaid by any number
of minor spikes.
Such output does not bother things like heaters,
transformers and motors, but can interfere with
TV reception and possibly damage sensitive
electronics equipment.
THE
FUEL
CELL
A BETTER SOLUTION
A better solution is the fuel cell. Its by-product
is virtually (and in some actually) zero noise and
only tiny amounts of totally pure water. Large
scale units have existed since the 1970s but
portable-generator equivalents have been snail-
like to evolve.
The methanol-fuelled EFOY ranges work well, but
the methanol must be of ultra-high quality, and
bought from EFOY as a condition of warranty.
The long awaited LP gas Truma Vega unit
(announced in 2002) was on sale briefly around
2012. They worked superbly but proved far too
costly.
The currently most promising LP gas alternative
is the USA-made WATT Imperium. It can produce
a continuous 500 watts (at a nominal 12 or 24
volts). It uses 0.0.015 kg/hour at 500 watt output,
and weighs about 21 kg. Its noise level is a mere
45 dBA – about that of a quiet whisper.
Many new fuel cells are under development.
If affordable, they will almost certainly wipe
fossil-fuelled generators off the face off
this planet.
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