Tag: wind power

The big bad nuclear mafia

Published by Johan on July 25, 2012

Quite often in the nuclear debate one encounters the idea that the nuclear industry is some industrial juggernaut of immense proportions, so large and rich that it can pay an army of lobbyists and crush the poor little renewable energy industry beneath its heel. Nuclear is firmly place next to oil, gas and coal in magnitude, richness and reach in the opponents mind. Renewable energy companies on the other hand are envisioned as small mom and pop buisnesses run out of the back of the yard with very small means and no political or economic clout to speak of. But what is it really like?

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Did you think renewable power is sustainable? Think again…

Published by Michael on February 14, 2009

“Sustainability” is a buzz-word these days. It is used often and eagerly, especially by opponents of nuclear power and proponents of renewable alternatives. There is an assumption to there that if something is renewable it is also automatically sustainable. There is also an assumption that nuclear power is not sustainable. How surprised people get when they find out that the exact opposite is true…

Let’s take a step back and for once examine what we actually mean by the concept of sustainability. In this article, we will be focusing on sustainable power production.

What sustainability is not

There seems to be a vague notion out there that something that is sustainable we can start using now and then keep using forever, or that something that is sustainable never consumes any resources. Well even by this faulty definition, renewables are not sustainable. This is because solar panels are not built from sunshine, nor are wind turbines built from a stiff afternoon breeze. You build them from consumable materials such as steel, copper, neodymium, gallium, arsenic, indium and other sometimes not too common materials. Also they have a finite life span after which they must be torn down and replaced. This means that solar and wind power does consume resources and in the end cannot be used forever.

But that is not the definition of sustainable, so let’s move on.

What sustainability is

“Sustainable development” was defined by the Brundtland-commission report “Our common future“ in June 1987 as:

…development that meets the needs of the present without compromising the ability of future generations to meet their own needs

Now let’s look at this. Does this say anything about renewables, using the same things forever, or even that using fossil fuels would be a bad thing? No it does not. The report doesn’t even say we cannot deplete a resource.

As for non-renewable resources, like fossil fuels and minerals, their use reduces the stock available for future generations. But this does not mean that such resources should not be used. In general the rate of depletion should take into account the criticality of that resource, the availability of technologies for minimizing depletion, and the likelihood of substitutes being available.

So what sustainability means is this:

We have needs, and we must meet them.
The future generations will also have needs, and we must not do anything that prevents them from getting these needs met.

People talking about sustainable development often talk about the future. But what they keep forgetting is that development that does not tend to the needs of the present as well, is not sustainable. Sustainable development must meet both current and future needs.

So now that we have established what sustainability actually means, let’s get to work applying it.

Applying the definition of sustainable to the real world

What are our needs when it comes to power? Among all needs, one is reliability.

Reliable power production means that we get have the amount of power we require, the instant we require it. Power is a perishable commodity. Especially electricity must be produced the very second we intend to consume it. If production does not meet demands, we have a power deficit. We do not accept power deficits. Not only is a power deficit annoying, but it can also be very dangerous as we are relying on electricity for a great number of critical applications, such as hospitals, tele-communications, cold food storage and pretty much anything that makes our society modern and thriving. Also power drops on the electrical grid risks damaging or destroying equipment connected to it.

Hence a source of power must be able to deliver as much as we want, the moment we want it or it is not, by definition, sustainable.

Are wind power and solar power sustainable sources of power?

Solar power and wind power are not living up to Brundtland commission definition of sustainable, for that most inane of reasons: when there is no wind, and when there is no sun, they do not deliver power. And by not doing that, they fail our need of reliability.

But surely there is always wind and sun, isn’t there? No, not always. Sun is a no-brainer, because sun does not shine 24 hours per day (except above the arctic circle in the summer but that doesn’t help us in the cold dark winter). So what about wind?

Wind power in Sweden, jan-feb 2009
Reported wind energy production in Sweden, Jan-Feb 2009

The graph above is statistics for wind power in Sweden, fetched from Vattenfall’s page www.vindstat.nu. This page represents day average wind power production in Sweden for 30 days. The reporting plants range all the way from the south tip of Sweden to the far reaching north. The image is a snapshot of the graph taken at February 14, 2009.

The amount of installed wind power, that is to say the maximum power capacity, that reports to this webpage was 695 MW for the 30 days displayed, which is about 85% of all installed wind power in Sweden. This means that theoretical maximum power production in this graph is 16 680 MWh per day. Keeping this in mind, we see that for January 25 to January 30, wind power delivered 2-4% of installed capacity. After that it made a skip up, but less than a week later is was down below 10% again for another four days.

And again we must remind you that this is day average production and does not consider fluctuations during the day. This means that wind power in Sweden at times most likely delivered less than 1% of installed capacity.

This means that development that would rely on renewables such as solar and wind to meet our power needs, would not be considered sustainable unless there was something else that could entirely replace them for low periods. Such replacements do not exist.

Are bio-fuels sustainable?

Bio-fuels is another renewable alternative that is getting much attention. Do they meet our needs? That can be questioned, because while reliability is acceptable, the guarantees of capacity are shaky at best. And even worse is that bio-fuels strike at one of our most basic needs: health and long life. Bio-fuels, just like any other combustible power sources, release gases and pollutants that are harmful to human health. While being mostly neutral when it comes to carbon balance, this does not make the emissions any less harmful to people. Improvements can be made, but it must be asked how many premature deaths we are willing to tolerate before the technology of bio-fuels have been improved to acceptable levels. Hence this leaves the sustainability of bio-fuels in doubt.

Is nuclear power sustainable?

Let’s look at the needs we have, and that the future generations will have:

Capacity
Reliability
Clean air, land and water
Health

Does nuclear power fulfill these needs? Yes it does. Nuclear power has a capacity and reliability that is matched only by hydro power and fossil fuels. It does not pollute air, land nor sea in such a manner that we cannot accept it. And it does not threaten health in such a manner we cannot accept it. In fact, the power it replaces, such as for instance coal plants, kills about 2 million people prematurely every year from air pollution. So in replacing that, nuclear power saves lives.

Nuclear waste is an issue, yes. But it is a solvable issue, solvable in such a way it will not impede future generations from having their needs met. The science needed to know how to do that has been available since the 1970’s. It is part needing to gather experience on how to do it, and mostly politics that has kept us from implementing them so far. But for instance the Swedish method for a deep geological repository KBS-3 is at such a level of maturity it may begin being implemented in the near future. And more alternatives for dealing with nuclear waste are being made available as technological development progresses. We have no reason to assume nuclear waste cannot be dealt with in a sustainable manner that meets the definition by the Brundtland commission.

If we use nuclear power, must future generations use it too?

Using nuclear power now does not force future generations to use it. Nuclear plants have a finite life span of about 40-60 years. For renewables like solar and wind, their life span is even shorter. After that, the plants must be replaced. The future generations are free to choose whatever method of production they want for these replacements. They are not locked in by our choice. If they want to use something else, they are free to do so.

And choosing something else, they most likely will. Fusion power has dodged us for some time, but the progress is very promising. The research facility ITER is being constructed as we speak. The follow-up DEMO is on the drawing board. If there are no big snags, work at these plants will be done by 2050, at which time fusion power can go commercial. If we are unlucky, it might be another 100 years before they work out the problems. Being pessimists, we can reasonably estimate that by 2150 at the latest, fission nuclear power, solar, wind and pretty much everything else we use for our base load, can be phased out. This is what the Brundtland commission report speaks of: “the likelihood of available substitutes”.

And even if fusion power never takes place, whatever opponents of nuclear power claim can be used to replace nuclear power now, can most certainly be used to replace it then. If not, their case falls apart anyway and we must keep using nuclear power and make it even more effective.

So does it really matter that we risk depleting our nuclear fuel resources? No, it does not. If we start to reach the end of such resources, something that is not likely to happen by at least 2 000-5 000 years anyway, then future generations may switch to whatever else they want to use. They are not bound by our choices, and as such, the definition of sustainable development is met by nuclear power.

Conclusion

It has been said that the person that stares too far ahead, risks tripping over their own feet. This is true also in this matter. We must not forget that our needs must also be met, and not just the needs of future generations. Otherwise we do not have sustainable development. And sadly, renewables such as wind, solar and bio-fuels do not yet meet these needs. No matter how much we spend on research, we cannot force the sun shine when we want it to, nor make wind blow on demand. Bio-fuels rely on combustion, which we do not know yet how to make non-hazardous to health. Hence they are not sustainable.

Nuclear power however is, as far as we can make out, sustainable.

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The day wind power nearly blew out Europe

Published by Michael on December 13, 2008

On November 4, 2006, Europe suffered one of the largest disturbances in its electrical power grid of the past half century. 15 million households were disconnected from the grid for 20-40 minutes. A trivial error that should not have meant any significant disturbances cascaded and spanned much of continental Europe. This nearly threw the continent into a blackout that would have dwarfed the North American power-out in 2003. While the direct cause of the 2006 disturbance was operator error, a root cause of the problem and a significant factor in delaying getting the grids back online, was wind power and combined heat and power (CHP) plants.

Background

The European power grid has been constructed, basically from scratch, since the end of World War II. The grid in itself is divided between a number of different Transmission System Operators (TSOs), like for instance E.ON (Germany), RTE (France) and TenneT (The Netherlands). Each country’s domestic power grid is serviced by one or more TSOs. In order to provide stability and safety of the power supply TSOs are connected to each other. The basic idea was that if an area suffers a major disruption, neighbouring TSOs can help by pushing power from their grids into the affected area.

However over time things have changed. With the increased use of supposedly more environment friendly power plants, such as wind turbines and CHP plants, coupled with requirements to cut down on emissions, TSOs today are required to accept power from neighbours if the latter has a surplus of low-emission power. While this sounds good in theory as it forces TSOs to use “greener” power, instead of for instance coal power, this means that the power grid is used in a way which it was not designed for. Shunting power from one area to another puts high loads on the power transmission lines. In effect the European power grid is often operated close to maximum of what it can handle. To rectify this problem, more power lines should be built, but this is becoming increasingly more difficult and thus we are stuck with the problem.

Due to environmental reasons, the development of the transmission system is more and more affected by stricter constraints and limitations in terms of licensing procedures and construction times. The reality today is that many UCTE TSOs face significant difficulties to build new overhead lines due to long authorization procedures and regulatory regimes.

Final Report
System Disturbance on 4 November 2006
union for the co-ordination of transmission of electricity

The windy weekend

November 4, 2006, was a Saturday. The event took place in the evening, starting at 22:10 CET. While power consumption is low in evenings and even more so during weekends, the load on the grid was still high. The reason for this was that TSOs use these low-periods to disconnect some power lines to perform maintenance on them. This means that remaining lines still operate at near full capacity even if demand is low.

Such conditions also meant that the fraction of intermittent and distributed power production such as wind and CHPs was higher than normal, something that was further compounded by the fact that Germany was experiencing windy conditions that evening. Large amounts of power was therefore being routed into The Netherlands and Poland, straining the power lines.

Problems begin

E.ON Netz was to disconnect a power line. Calculations had predicted that this should have been alright without compromising the safety of the power grid. However due to changes in the conditions – Germany’s unforeseen windy weather, and a rescheduling that was communicated late to the other TSOs – the disconnect and rerouting of power overloaded the remaining lines. These power lines tripped (automatically disconnected) in order to protect them from becoming damaged. This caused more overloads in other power lines, causing further trips. This is what is know as a cascade. The cascade had within seconds divided the European power grid into three isolated “islands”: west, north east and south east.

The disturbance of nov. 4 2006 divided Europe's power grid into three parts — The severe disturbance of nov. 4 2006 divided Europe

The west area, having lost the connection to eastern Germany where much power was coming from, suffered a large deficit in power production. In order to protect the power grid and equipment connected to it, TSOs started load shedding, that is to say they started disconnecting customers from the grid in order to lighten their load. For each TSO 3-20% of all customers were disconnected and suffered power outs. In total approximately 15 million European households were affected by this.

In the north east area, the problem was the opposite. With the consumers in the west disconnected, the power generators surged as there was no-one that could accept the power they produced. Windmills are particularly sensitive to this and automatically disconnected from the power grid. Within a minute the north east area stabilized.

The south east area suffered a rather small power deficit in comparison and the impact was therefore smaller.

Trying to get back online

The west area started up power generation reserves to counter the production deficit. Within fifteen minutes the west area had stabilized to nominal production, although they were still disconnected from the north east.

In the north east however the different TSO operators had big problems. This was because the windmills and CHP plants that had tripped, automatically reconnected themselves, again causing a production surplus. There was no way to keep the windmills from doing this. To counter it the TSO operators had to manually prevent overloading the grid by instructing other power plants to cut down on production or shut down completely, and engaging power buffers such as pump storage units. This was while they at the same time tried to diagnose what had happened and why they had a disturbance in the first place. There was much confusion and which meant that the north east area was delayed in getting things back to normal.

In order to help counter the production surplus from the uncontrollable windmills, the control block leader for CENTREL (TSOs in Poland, the Czeck Republic, Hungary and Slovakia) somewhat unconventionally agreed to accept much of the surplus. However this meant that huge amounts of power was suddenly being routed eastwards, overloading some power lines up to as much as 140% of normal capacity, severely risking splitting the power grid again. Luckily this did not happen.

As the power levels were restored they tried to get the different areas connected again. Starting at about 25 minutes after the problems began, they tried to resynchronize the different networks. However for another quarter hour, the networks would not connect to each-other because they were fluctuating too much or not lining up to each-other. Either they wouldn’t even attempt a connection or they would trip out again after a few seconds. At 22:47 did the networks begin to connect properly, and not until over an hour later, at 23:57, were things back to normal.

Conclusion

Opponents of nuclear power and proponents of “green” power such as wind and CHPs often argue that nuclear power leads to poor safety and reliability of the power production. The argument is that “putting all eggs in one basket” puts us at a risk of a serious power shortage. They argue that distributed power such as wind is better because it spreads the risk.

However the events of November 4, 2006, point to the exact opposite. While the grid was always made to handle large single-point outages, such as a nuclear power plant going offline, with fairly local load balancing, it was not made to being operated the way we are forced to do with intermittent power. With wind power being essentially uncontrollable and fluctuating there is a need to shunt power long distances through power grids that were never built to handle it. This in turn puts strain on the grids, lessening the margins and risking cascading chaotic failure of an entire continent.

With increased use of wind and other intermittent power sources, this risk can only be increased unless we basically tear out our entire transmission grid and build a new one. This is an investment that will not come cheap. Those arguing for large scale power production using intermittent sources, such as wind, must seek an answer to the following question:

Is it prudent, economical, or even feasible to replace the entire power grid of a continent, just to accommodate a notoriously troublesome source of power?

/Michael Karnerfors, for Nuclear Power? Yes Please

Source: UCTE – Final Report, System Disturbance on 4 November 2006

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