Energiewende and the problem of intermittents

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From the course by Universitat Autònoma de Barcelona

Sustainability of Social-Ecological Systems: the Nexus between Water, Energy and Food

13 ratings

Universitat Autònoma de Barcelona

Sustainability of Social-Ecological Systems: the Nexus between Water, Energy and Food

13 ratings

In this course you will become familiar with the ideas of the water-energy-food nexus and transdisciplinary thinking. You will learn to see your community or country as a complex social-ecological system and to describe its water, energy and food metabolism in the form of a pattern, as well as to map the categories of social actors. We will provide you with the tools to measure the nexus elements and to analyze them in a coherent way across scales and dimensions of analysis. In this way, your quantitative analysis will become useful for informed decision-making. You will be able to detect and quantify dependence on non-renewable resources and externalization of environmental problems to other societies and ecosystems (a popular ‘solution’ in the western world). Practical case studies, from both developed and developing countries, will help you evaluate the state-of-play of a given community or country and to evaluate possible solutions. Last but not least, you will learn to see pressing social-ecological issues, such as energy poverty, water scarcity and inequity, from a radically different perspective, and to question everything you’ve been told so far. ACKNOWLEDGEMENT Part of the results and case studies presented have been developed within two projects: MAGIC and PARTICIPIA. However, the course does not reflect the views of the funding institutions or of the project partners as a whole, and the case studies were presented purely with an educational and illustrative purpose.

From the lesson

Module 4. The challenge of energy accounting

This week we will look at energy. As we did for food, we will start by looking at the problems of energy accounting, and setting a framework to allow us to carry out energy analyses across levels and scales. You will see why energy accounting is one of the most problematic aspects of sustainability, and through the example of the Energiewende we will explore how this affects policy.

Energy efficiency for policy targets12:46

The problem with agro-biofuels13:58

Energiewende and the problem of intermittents9:23

Meet the Instructors

Mario Giampietro
ICREA Research Professor
Institute of Environmental Science and Technology (ICTA)
Andrea Saltelli
Guest researcher
Institute of Environmental Science and Technology (ICTA)
Tarik Serrano
Post-Doc Researcher
Institute of Environmental Science and Technology (ICTA)

OK. Welcome back to the lesson on

a critical appraisal of existing narrative on alternative energy sources.

This is Session C, in which we will discuss

or illustrate the problem experienced by intermittent giving,

an explanation based on metabolic thinking.

In particular we would use the Germany's Energiewende as a case study.

To start the discussion we can have,

this is a provocative figure generated by a Morgan Private Bank report.

And the propagation is that you know,

we have a lot of forecasts about

the quick takeover of alternative electricity in the United States,

but as a matter of fact,

after all these years,

the electricity produced with alternative sources is still below 10%.

And what is really scary is that these 10% include hydropower,

which is the most important source of electricity or alternative electricity.

If you're looking at the situation in Germany,

things are not getting better in the sense

that after the big investment in the Energiewende,

it is true that there is an increase in the amount of electricity

from alternative energy but it's also true that this didn't cut

the emission and this is generating major troubles for

the economic viability of conventional power plant.

So what is the problem?

Again, what I would like to illustrate here is how a thinking

based on the concept of metabolism could help in having a better framing of the problem.

So the major problem is that in reality we are not talking about electricity.

It is not about producing an amount of electricity per year.

It is about matching the supply and demand

at a much smaller scale over hours or even minutes.

So if you are looking at the amount of energy produced and consumed,

this is something which can be of

selection process 73 to 150 gigawatt and is changing quite rapidly during the day.

This is during a week and you can see even during the day there are big changes.

So what is the problem?

Getting back to flow fund relation,

we have two types of flows

and two type of fund element that are needed to generate these flows.

So there is no electricity.

There are two types of electricity and there are two types of power plants.

Lets look at a hypothetical,

I made it up,

the curve of consumption or demand of electricity has to be matched.

We can have a plant.

They are not very flexible in changing their outs,

the supply but they are very efficient so we can use them as

a base loader to go over the majority of the demand and then you have other plants.

They are quicker in starting and producing electricity and adjusting and maybe they are

used less during the years

so in a way you are not taking full advantage of the investment of capital.

So you need two types of power capacity for these things.

You would have nuclear,

coal, brown coal plants that you can use a lot.

I asked base loader, you see these are the one covering these base load.

These are huge plants.

You can now switch on and off nuclear plants these days to get

these big plants in production.

On the other hand, you have other power plants then natural gas turbines,

you can push the button and it's immediately online

or either you just open the water going

through the dam and you can produce with very small time of regulation.

So what happened here,

that if you're looking at intermittent,

the intermittent need the biggest loaders.

They are not producing what is needed and they produce not necessary when [inaudible].

To visualize this, that this is the Peakers here are used

very little during the year and this is not because they are the best plant but

simply because they are performing a different function.

They are capable of adjusting at a very small time.

So, let's imagine now that we are trying to use intermittent into the grid,

in spite of the fact they are neither peaker or loader.

So how can we do it?

Either we are not giving priority so

they are producing when this is useful you are using it,

otherwise you don't or you can see that

intermittent are given priority in

the grid and this is more or less what happened at Energiewende.

So you are forcing the system to use the energy produced by intermittent.

In the case that the intermittents are not given priority,

you have the base load on the bottom,

then you have intermittent on the top and you can

see that you still need peakers because the peaks are not

covered and the large fraction of electricity

produced by intermittent is not used because it's produced when there is no demand.

Of course you cannot use it here because

the baseloaders are covering already the energy required.

So most of the electricity produced is wasted.

What happens if we increase

the power capacity of these intermittent and we put more intermittent.

So if we put more intermittents they keep

producing what is not needed so basically is not solving the problem.

The second possible option is that to add intermittent given priority so

basically the peakers remain there

and we have the intermittent used as loader on the bottom.

And this is much better because we can use all the electricity produced by intermittent.

But we leave some hole here and there and that we still

need backup of coal fired or nuclear or whatever to avoid blackouts.

So what is the problem here?

That's basically the solar and wind capacity goes up.

You are building more panels -- photovoltaic panels,

more windmills -- but you still need all the thermal capacity that was before.

And this is what is generating the problem of CO2 emissions.

In Germany, what happened is that they switched to

a smaller plant called brown plan to reduce the cost,

and of course the big power plants have to remain on even when they are not used.

So their emissions remain even though we are using the electricity from renewable.

So what is the problem is that in the modern electric sector

cannot afford cheap and reliable electricity.

So the real issue here is to have reliable production of wind.

I mean we have to find a way of backing up intermittents.

One way that we are considering is the 12 batteries.

This is where a lot of research is going on.

And then all matching with the more natural gas that

may be able to have a better complementation between

the intermittents and the required peak capacity.

It would be important in the future discussion about this,

is that we have to keep in mind there is not electricity and there are not power plants.

They are baseload power plants and peakers,

and if we do not change that situation,

intermittent per se are not functional because

they either produce electricity that is not

needed or when they are used as a main given priority,

then they still require back-ups.

So they are not solving the problem.

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