🚀 go-pugleaf

Tim O'Flaherty wrote:
> 
> Greig Ebeling wrote in message <393e22ee.49400070@news.bigpond.com>...
> >On Wed, 07 Jun 2000 02:10:05 GMT, kinsler@frognet.net (Mark Kinsler)
> >wrote:
> >
> >>Greig Ebeling <greige@bigpond.com> wrote:
> 
> Yet wind power schemes are
> >theoretically able to produce no more than a few percent of our power
> >before becoming uneconomical.
> 
> What "theory" are you refering to?  Do you have references and data to back
> up this assertion?  What specifically is  "a few percent"  ?  2%,  5%, 80%
> ?

"The levels of electricity generation from intermittent sources (for
example from wind turbines or photovoltaic arrays) that can be accepted
in a supply system depend strongly on the nature of the system and the
measures that manage time variations in load.  Typical percentages of
wind or solar shares in systems without storage are about 20% for grid
systems and up to 50% for large systems with reservoir based hydro or
time zone variations of loads (Sorensen, 1981, 1987; Grubb and Meyer,
1993; Kelly and Weinberg, 1993).

"Short-term storage will ease regulation and possibly improve power
quality, but only intermediate and long-term storage will allow large
systems to have shares of variable renewable-energy sources that
significantly exceed 50% (Jensen and Sorensen, 1984).

"The SUTIL simulation model (Kelly and Weinberg, 1993) calculates the
average cost of electrric generation as the result of an hour-by-hour
simulation that takes into account demand, the variable output of
intermittent renewable equipment, the load-leveling capabilities of
hydroelectric facilities, and the dispatching characteristics of
alternative thermal-electric plants.  Results of a SUTIL simulation of
10 alternative portfolios for a hypthetical utility--based on assumed
values of the demand load profile, insolation, fuel costs, and capital
costs--are shown in Figure 19-4.  For this set of alternative utility
investment portfolios...  the fraction of electrical energy provided by
intermittents can rise up to about 30%, without the use of new
electrical storage technology, before costs start rising significantly."

IPCC 1996 _Climate Change 1995: Impacts adaptations and mitigation of
climate change_ pp. 617-619

Sorensen 1981 A combined wind and hydro power system. _Energy
Policy_9(1) 

Sorensen 1987 Current status of energy supply technology and future
requirements _Science and Public Policy_ 14

Grubb and Meyer, 1993 Wind Energy: resources, systems, and regional
strategies. In Johansson et al. (Eds) _Renewable Energy: Sources for
Fuels and Electricity_ Island Press, Washington DC

Kelly and Weinberg, 1993 Utility strategies for using renewables. In
Johansson et al. (op cit)

Jensen and Sorensen, 1984 Fundamentals of energy storage.  John Wiley &
Sons, New York NY

-dl