From: John De Armond
Subject: Re: Power, was Re: Propane prices
Date: Mon, 08 Jan 2001 23:29:06 -0500
"George E. Cawthon" wrote:
> Sorry Will, but you obviously don't know anything
George, if you stop right there, you can generalize it and still hit
the nail on the head.
> about the PN, about
> how paperplants operate here or about the electric power generation
> here. Ralph is dead on.
> I don't know how you define cogeneration, but I think we define it in a
> quite different manner here and the requirement of major power producers
> to buy cogeneration is usually a drag and not a benefit to the consumer.
He obviously doesn't have a clue as to the definition of
co-generation. "Co-generation" to utility people means a facility
generating part or all of its power. Typically we think of Cogen as
involving using otherwise waste material or heat but not necessary.
Utilities heavily encourage industrial Cogen.
There are a variety of terms to refer to what you're talking about,
George, the forcing of utilities to buy "toy power" from alternative
generators. When I worked for TVA, we called 'em "Alternative
Generators". Another commonly used term is "small source
Last professional job I did before retiring to the pig palace was to
join a friend in a project to automate the power plant at the
Westvaco kraft mill in Charleston, SC. I still occasionally consult
to the Bowaters newsprint mill just up the road in Charleston, TN.
The mills are quite similar in their energy needs and management.
(All of this is of about '92 of course.) At Westvaco, there are 6
boilers and 5 turbines with a rotating capacity of about 150 mw.
The mill uses around 150 mw when all lines are running. The mill
generates enough waste to make about 50 mw. They have a negotiated
price deal with the utility to receive and pay for 50 mw 24/7. They
pay whether they use it or not. The deal calls for large surcharges
for anything OVER 50 mw. In other words, the utility gives them a
favorable price in return for becoming a curtailable base load. The
objective of our project was to run the boilers on whatever
combination of fuels necessary to keep the utility load at exactly
50 mw. A whole bunch of Allen Bradley/Hewlett Packard hardware and
a BUNCH of HP-UL software later and that's exactly what we did. The
boilers are each optimized to burn a particular fuel, be it bark and
chips, saw dust, black liquor, gas, oil or coal and are capable of
burning at least two other fuels each. Our control system fired
boilers and brought generators up and down as needed, depending on
plant load, available waste stream, spot fuel prices and a couple
dozen other parameters specified by the plant. And if the utility
needed to shed the mill during an energy crisis, the control system
would either increase firing or send shutdown signals to various
parts of the mill to enable the mill to run completely
I can guarantee that if SC was deregulated and spot power rates were
approaching $1k/kwh as it is in Ca during peak loading, Westvaco
would shut down the mill and send 150 mw out on the grid. Hell,
they could burn Chanel No. 5 and make a profit at Ca spot market
The mill had an impromptu dry run during the last BIG hurricane that
hit Charleston. The storm took out all the power in the area. The
mill had gone to hurricane safe shutdown but the power plant was
running. Unbeknownst to the mill powerhouse operators, the
utility's reverse current relaying didn't work and the mill was
supplying power to all of the city of North Charleston. That
apparently went on for the better part of the night before someone
figured out what was going on. Seemed to work quite well.
A much more recent project in which I oversaw the startup testing
and certification involved cogeneration but no waste heat or fuel at
all. It involved installing a 0.5 mw diesel generator at a job shop
fabricator to run a huge stamp mill. The stamp mill would draw
almost that much power for a couple of seconds on each cycle. The
idling power was under 5% of that but the power factor was very low
because the motor was under-loaded. Not only would the utility have
nailed them a HUGE demand surcharge, it would also nick them a
second surcharge for power factor. It turned out that a generator
to supply this load was cheaper than the surcharges and/or
alternative power storage schemes and power factor correction.
Caterpillar makes a genset just for these applications. Large
flywheel mass, very low off-load BSFC and multiple fuel capability.
The particular generator chosen burns either diesel or natural gas.
IOW, it burns prime fuels but is cogen nonetheless.