Friday, September 21, 2012

14 November 2011 – Electrical Balancing Acts

UPDATE:

And the better the wind turbines work, the worse for the grid:

Thanks to a flood of subsidies unleashed by Angela Merkel’s government, renewable capacity has risen still further (solar, for instance, by 43 per cent). This makes it so difficult to keep the grid balanced that it is permanently at risk of power failures. (When the power to one Hamburg aluminium factory failed recently, for only a fraction of a second, it shut down the plant, causing serious damage.) Energy-intensive industries are having to install their own generators, or are looking to leave Germany altogether.
Wind power - "renewables" in general, with the sole exception of hydroelectric power - is an unmitigated disaster, and one that would not have occurred without heavy government subsidization. It proves an old adage: that whatever sort of behaviour you subsidize, you inevitably get more of. Germany's renewable energy sector is performing so grandly that Germany is planning on vastly expanding its coal and gas-fired generation in the coming years.  And I'll bet you dollars to donuts that Merkel's hasty and ill-advised post-tsunami "no nukes" pledge won't last another year. Japan has already backed away from theirs.

It's an ironic lesson - that for a modern industrialized society, from a perspective of grid management, getting any more than a tiny proportion of electricity from intermittent and inherently unreliable "renewable" energy sources is quite simply...unsustainable.

Of course, the United States, thanks to Barack Obama's policy of using EPA regulatory action to effect fundamental policy changes (like his maniacal and grotesquely unscientific jihad on carbon dioxide) that he could not achieve through legislation, is going in precisely the opposite direction:



Look, folks, I am in this field. I have been for more than 30 years. Losing 36,000 MWs of the most cost-efficient generation capacity in the US is a disaster. You have no idea how bad the increases are going to be. They will be disastrous to the individual energy consumers and apocalyptic to large users – those who create jobs.



I shudder to think of what this is going to do to grid reliability as well. A lot of those coal plants help support the grid during disruptions. They regularly provide both energy and MVARs (Mega Volt-Ampere Reactive) that keep the grid from collapsing when large loads are added or lost. (That’s about as simple as I can make it and still be understood.) Losing these stabilizers will make it very hard to hold the grid. I pity the load dispatchers.



Trust me, people, this is a very big, very bad thing that is happening as a direct result of Barack Obama’s war on coal.

Funny how it always comes back to November, doesn't it? If you think the last four years were bad for our cousins to the south, just imagine what will happen once Obama is no longer constrained by worries about re-election. I'm still not convinced that Obama is deliberately trying to destroy the United States of America, but I keep coming back to the same question: if he were, what would he be doing differently?  As Conrad Black put it so succinctly Friday last,

If this administration is re-elected, Canada, as it has for the entire mighty spectacle of the inexorable rise of the United States, will have the ring-side seat for a disaster.

Amen. Let's hope the adults seize the wheel, jettison that clown and his cronies, and start the long, hard slog of putting America back on the road to sanity.


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Colleagues,

If strategic analysis areas of interest could be represented by a Venn diagram, one of the most interesting areas of overlap would, oddly enough, be in electrical grids.  I've written about grid structures and problems before, but the subject is worth thinking about at length.  The average grid in Canada and the US these days accepts power generated both from traditional (thermal, hydroelectric, and nuclear) and 'green' (wind, solar, biomass and so forth) sources.  Thermal generation from coal, oil, and natural gas evokes Middle Eastern nations, Islamism, terrorism, environmental damage, sulphur dioxide emissions, acid rain, China's exploding power demand (and its equally exploding coal-fired generating capacity), health problems, the 'Asian Brown Cloud', oil tankers, oil spills, drilling moratoria, pipelines to the US, pipelines to the west coast, wildlife preserves, aquifers, and a host of other topics.  Hydroelectric generation engages questions of rainfall and snowfall, melt dates, water levels, water usage, droughts, irrigation, sedimentation, critical infrastructure protection, species preservation, and massive civil engineering projects.  Nuclear power engages proliferation concerns, supplies of uranium ore, enrichment technologies, Iran, nuclear weapons, nuclear wastes, nuclear waste transport and storage, regulatory issues, more terrorism, earthquakes, tsunamis, leaks, Three-Mile Island, Chernobyl, arms control, arms reduction, pre-emptive strikes, Russian collaboration, and (once again) the Middle East.  And 'green' energy sources involve so many ancillary considerations that there's no point trying to list them here.

This is why it's fascinating to take a look at where all of these factors come together - in the massive minute-by-minute balancing act that's necessary to keep a large electrical grid system operating in the face of complex and shifting loads, supplies, and environmental factors.  Forbes recently published an article looking at how the Bonneville Power Administration, which manages water flow on the Colorado River and powers a large part of the US Pacific Northwest, manages to keep the power supply available and balanced. 

The article can be found here:

http://www.forbes.com/sites/jonbruner/2011/10/20/the-high-stakes-math-behind-the-wests-greatest-river/

It's a great example of engineering hoo-rah (the author had me at "five-ton circuit breaker"), and worth a read for that reason alone; but from a strategic analysis perspective, one of the graphics in particular caught my eye.  It was this one:


That's one week in the life of the Bonneville Power Administration (BPA - not to be confused with bis-phenol A, the chemical that's had legions of nervous nellies chucking their plastic kettles out for the past decade).  It's the week that took place exactly one month ago, to be precise [ACTUALLY, 14-21 OCTOBER 2011 - ed.). 

That graph tells us a whole lot of really important things.  The first thing it tells us is that electrical demand - the scarlet line - is actually incredibly predictable.  There's a fascinating lesson here.  At its most basic, nuclear fission is random chance; but if you assemble enough, say, uranium atoms in one place, they demonstrate statistically predictable behaviour.  Same with people.  You or I can decide whether or not to flip a light switch on or off; it's a matter of personal choice, and your choices (and mine) may be utterly unpredictable.  But if you assemble millions of people, their behaviour - for example, in consuming electricity - starts to become statistically very predictable.  As the scarlet line shows, there are predictable demand surges in the morning, as people are preparing to go to work, and in the evening, as they make dinner and perform other chores; and there are predictable declines in demand: a shallow one at lunch time, and a much larger one over night.  Moreover, those demands don't vary greatly from workday to weekend.  If it weren't for the day notations on that chart, you'd be hard-pressed to tell Friday from Saturday.  It's easier to make out Monday and Tuesday by the early morning peaks - although it's interesting to note how that peak, which starts off high on Monday, declines daily through the week, until the Friday morning peak is within a few percentage points of the Saturday morning peak. I guess that's not really surprising, is it?

The brownish-red line is interesting, too.  That's thermal generation, and most of the time it's remarkably steady.  This is because thermal power plants, all of which are basically steam turbines, operate most efficiently when they operate at continuous output.  Boilers, after all, have to be brought up to operating temperature, and take time to cool down.  Some thermal plants - small, gas-fired turbine plants, for example, which are basically jet engines hooked up to generators - can start up and ramp down quickly, but doing so tends to be costly in terms of fuel.  Imagine powering your house by generating electricity from a jet engine; actually, those of us who worked in ADATS units don't need to imagine it, because each ADATS vehicle had a jet engine hanging off the front of it, and burned 1300 litres of diesel every 24 hours just to keep the lights on.  It's effective, but it's not cost-effective, to start up and stop in response to unpredictable shifts in demand.  As a rule, thermal plants work most efficiently, and get the most electrical power out of the heat content of their fuel, when they maintain continuous, stable output.

The blue line - hydro plants - are the exact opposite of thermal plants.  Hydro power is pretty much the most efficient source of generation on Earth.  It's essentially solar power, with the motive force for electrical generation provided by potential energy brought to us courtesy evaporation, condensation and precipitation.  The water is stored behind dams, and can be released through turbines to generate kinetic energy (in the form of spinning turbines driving generators to push electrons through a wire) pretty much at will.  Hydro power is extremely responsive, able to ramp up and down in a matter of minutes to respond to changes in demand and supply.

The green line is the wild card in the deck.  That's wind power.  The BPA has about 3500 MW of wind power installed, roughly equivalent to about 2000 large turbines.  That green line tells you everything you need to know about the complexities that government-subsidized wind farms have introduced into the grid management equation.  On the 14th and 15th of last month, the BPA's wind turbines were basically flatlined.  On the 16th, there was a brief spike in production.  The turbines put out a little bit of power - about a quarter of the installed capacity, which is par for the course for wind turbines - over the night of 17-18 October.  And then, on the afternoon of the 19th, Gaia cut loose and the wind productivity soared. 

Look what happened to the rest of the grid.  In the space of about an hour, electrical generation from wind turbines went from nothing to about 85% of nameplate capacity - and in that same hour, demand actually fell, by about 200 MW.  Thermal plants were running as usual, providing baseline power, and hydro plants, being the most flexible, were going through their daily double-hump routine to take care of the morning and afternoon demand surges.  Just before lunch, when demand was falling, wind power production exploded, dumping 3000 unneeded MW into the grid.  Hydro generators had to be shut down as quickly as possible to avoid catastrophic oversupply (which can trip circuit breakers and cause wide area power outages); and because that wasn't enough to stem the flow of power, even thermal plant output had to be scaled back, greatly reducing efficiency.  And then, five hours later, as the wind died back down to nothing, hydro and thermal plants had to be brought back on line.

The problem is that while we can predict demand with reasonable accuracy, we never know when the wind's going to blow, or how hard, and when it's going to stop blowing.  This means that wind power can never be a replacement power source; it can only be a supplemental power source.  And because it's entirely unreliable, you cannot afford to take a single MW of conventional production off line unless you feel like explaining to Missus Miggins why she can't boil water for tea.  Moreover, because wind power is an unpredictable, supplemental power source, your grid system has to be flexible enough to be able to accept unpredictable injections of power - which means that your conventional production capacity has to be rapidly scalable both up and down.  As the graph and the BPA experience demonstrates, this is a costly and technically challenging problem, principally because power generation has always been designed to operate continuously, because that's what's most efficient.

It's funny, isn't it, how whenever policy and ideology bump up against the real world, the resulting problems are ALWAYS 'costly and technically challenging'?

And if you think managing the northwest power grid is complex now, wait until 2013, when BPA is supposed to have twice as much wind capacity installed - 6000 MW, if current plans don't run headlong into looming fiscal realities.  If 6000 MW of wind power were to suddenly come on line at a time of low demand, the rest of the conventional generators would have to have the capability to drop to virtually zero output in a matter of moments - and to then come back on line as soon as the wind died down.  If you need a visual image, think about a Nascar race with 50 competitors on the track, moving at full speed, inches away from each other, and a rule that requires the marshal to always have between 49 and 51 cars on the track, no more, and no less.  Now, without warning, 25 more cars come in from an injector lane, moving at full speed, and the race marshal has to get 25 of the original competitors off the track in a matter of seconds, without letting anybody bang into each other.  And then think about what happens if the new arrivals suddenly off-ramp without warning, and the marshal has to feed an unpredictable number of the original drivers back onto track, ensuring that the total number of cars never gets outside of the 49-51 mandatory total.

If that sounds impossible consider the fact that it's far too restrictive an analogy, because the energy of the moving electrons that the BPA grid handles every minute is roughly equal to the amount of kinetic energy of about 21,000 stock cars moving at 200 km/hr.

I'd say that's quite a balancing act.

What's the strategic analysis angle in all this?  Well, many of the proponents of wind power are selling it not only because of its supposed environmental advantages (on that point, you might want to google "China cancer city"), but as a solution to the problem of "energy dependence" for the US.  Really?  Only 18% of the petroleum imported by the US last year came from the Persian Gulf (25% came from Canada); but 75% of the world's supply of neodymium-iron-boron magnets (the key enabling technology for the newest generation of direct-drive wind turbines) and 60% of the world's supply of samarium-cobalt magnets (the key enabling technology for older, geared wind turbines) comes from China - which also, not at all coincidentally, produces 97% of the world's supply of neodymium and samarium.

It's almost as if the US government asked itself whether it wanted to be 18% dependent on Saudi Arabia for its energy needs, or 97% dependent on China, and settled on the latter.  Come to think of it, that's kind of a balancing act too, wouldn't you say?

Cheers,

//Don//