Re: Using nuclear power to make renewables and a hydrogen economy cost effective

From: Alex Terrell (alexterrell_at_yahoo.com)
Date: 10/28/04 

Date: 28 Oct 2004 02:00:47 -0700

"Ian St. John" <istjohn@noemail.usa> wrote in message news:<BuQfd.11413$Qs6.1157793@news20.bellglobal.com>...

> > Another alternative would be to skip hydrogen and use biodiesel in
> > diesel-electric cars and machinery, and use nuclear, solar, wind, and
> > hydroelectric power for industry and domestic use. Both would result
> > in closed carbon cycles.
>
> What makes you think that the 'hydrogen economy' will be exclusively hydogen
> based? Do you think that the current 'oil economy' does not have instances
> of methane digesters, wind power, etc? It is most likely that a hydogen
> economy will generate hydrogen to fuel fixed power consumers such as
> factories, as well as short haul transportation such as commuter and public
> tansit traffic which can be refuled by pressurization.

Under most, non fossil fuel scenarios, electricity will be cheaper
than hydrogen, so as today, electricty will power fixed installations.
It could also be used to power short haul transportation - plug-in
hybrids could have a range of 50 to 100km.

Heating and long haul transportation are tricky. Currently, gas
heating is about 1/5th the cost of electricity.

Cars will probably be
> 'dual fuel' with biodiesel for long haul and hydrogen (tapped from the house
> supply) for short trips.
>
Under current scenarios, we can't get enough bio diesel to satisfy the
mortorist. However, with plug-in hybrids, ~90% of journeys and ~50% of
mileage could be done on grid powered batteries. For the rest, we have
a doubling or in efficiency compared to todays cars (a trebling
compared to most US cars).

> >
> > I think much of the emphasis on hydrogen fuel cell technology is
> > being a red herring for those who do not want fuel effecient vehicles
> > in the immediate future- the oil industry and auto manufacturers.
>
> Certainly. The efficiency of ICE engines fueled by hydogen is not much
> different from the current efficiency of PEM fuel cells. The real key to
> efficiency is the hybrid car, that can conserve energy instead of wasting
> it. I suspect, though that fuel cells are prominent because they have the
> *potential* for 80%+ conversion efficiencies while the ICE is limited to a
> much lower value by thermal laws.
>
I read pure hydrogen fuel cells can manage 80%, even today. But there
are a lot of problems with this, which is why BMW is pushing for
hydrocarbon fuel cells which do about 40%.

I agree about the hybrid. Even if we have perfect fuel cells, the cars
would still be hybrid. But I also think the future is plug-in hybrid -
most people could do most of their driving on a night time charge. (In
Europe, at 1/10 th the "fuel" cost of today's vehicles using highly
taxed fuel).

> > They can keep saying "hydrogen is right around the corner" till the
> > cows come home. In the meantime, we have technologies to make cars
> > average 55-100 mpg, such as gas-electric and diesel electric hybrids.
> >
> > And with biodiesel, it will be a closed carbon cycle.
>
> Note that there is a process of steam reforming recently announced that can
> turn vegetable oil into very clean hydogen. The two are not that far apart.
> I would include 'cellulose ethanol' from bio waste in that asessment, by the
> way, for portable fuels.

I have seen figures implying that the land area required would be
impossible large. Perhaps GM products can help, but in any case,
farming tends not to be good for the environment.

And Ian, thanks for the constructive input.

Relevant Pages