Bjelkeman's travel notes

Travels with the cloud in my pocket.

Sustainable energy – Sweden’s electricity supply (part 3)

To understand how to make the Swedish energy system sustainable, we need to now look at how much is sustainable already and how much needs to be replaced by sustainable sources.

So I am starting with the easy part and look at the electricity supply. Sweden already have a significant component sustainable electricity production, primarily from large hydro, but also from biofuels which power the district heating systems (cogeneration). Smaller sustainable components are wind power and other cogeneration.

SE Electric production

Figure: Sweden’s electricity production per production method and total consumption, 1970-2013, TWh. Figure from Energiläget 2013, part of figure 12.

In this figure we can see that the Swedish electricity consumption is about the same in 2013 as it was around 1987, at about 140 TWh. It peaked in 2000 at about 150 TWh. In 2013 hydro power supplied about 55% of the Swedish consumption and nuclear power supplied about 43%. One should note however that a few years ago they were about equal. It depends on a number of things: how much water is available in the dams and also maintenance cycles for the nuclear power plants, which sometimes need to be shut down for long periods for planned or unplanned maintenance.

In both 2012 and 2013 Sweden produced more electricity than it consumed. In 2013 the overproduction was about 20 TWh (about 12%) more than consumption and this went on export. So it is probably more accurate to say that hydro supplied about 49% and nuclear about 38% of Swedish electricity consumption.

Cogeneration or combined heat and power (CHP) supplief the next biggest part, combined about 20 TWh. However, we can’t really say that this is sustainable, as this graph doesn’t say anything about the energy source used in the CHP plants. We have to refer to another graph to puzzle out that. Wind power provided about 10 TWh in 2013. [1]

So for the sustainable component of this I am going to count:

  • Hydro power: 140 TWh [2]
  • Wind power 10 TWh
  • Some portion of the cogeneration, see later blog for how much

Probably a bit controversially I am going to count nuclear power as a transition system to be phased out later. Nuclear power is a fossil fuel, but it doesn’t produce the huge amounts of climate changing emissions that other fossil fuels produce. So it makes sense in my personal opinion to phase the nuclear power out last, as I wrote about earlier.

For the next blog I’ll investigate the sustainable component of the cogeneration.

Links to the previous posts in the series

[1] My household electricity is 100% wind power, from the wind power cooperative OX2, where I have enough shares to supply 90% of our yearly consumption from our own shares.
[2] Large hydro, like most of the hydro power in Sweden is not really considered sustainable anymore. The dams destroy an awful lot of the ecosystem when they are put in place and in Sweden only old large hydro stations can be considered “sustainable” and if you build new once then they aren’t. However, there are essentially no further rivers to dam up anymore in Sweden anyway, so it is a bit of a non-issue.

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Sustainable energy – a Swedish energy balance sheet (part 2)

SE Energy balance

So here is my translation of the chart (from the previous blog post) “Total slutlig använding updelat på sectorer, 379 TWh” which in English is “Sweden – Total energy use of energy, divided by sector, 379 TWh (2011)” with added country and date for clarity.[1]

I have changed the colours in the chart, as I didn’t think they were as informative as they could have been and I have made a key for it, which is somewhat subjective.

  • Black: Coal and coke, arguably the worst fossil fuel.
  • Grey: Oil, the second worst fossil fuel.
  • Olive green: Natural gas & coal gas, the least bad fossil fuels in this overview.
  • Yellowish: Biofuel and peat [2], better, but still bad air pollutants. Also the energy economics in some biofuels is questionable.
  • Light green: District heating, better, but is often a mix of biofuels, waste and some fossil fuel.
  • Bright green: Electricity, best, as it can easiest be converted to solar or the other least polluting energy sources. (Even though it is 46% nuclear in 2014.)

So what does this picture tell us?

Clearly transport has the biggest challenge, as oil is so prevalent. The industrial sector in Sweden has moved strongly towards biofuel and peat, but there is still quite a lot of fossil fuel in the mix. The residential and services sector is doing relatively well with only 10% of fossil fuel left in the energy mix.

It is also interesting to see categories which are nearly the same but not quite, like renewable fuel in the transport category, but bio fuel in residential services and biofuel and peat in the industry category. Which sometimes makes it harder to compare. Also district heating could well be run on coal, biofuel or heat pumps, all which have a very different environmental impact. Ideally district heating should be divided instead over the different fuels.

Electricity can also contain fossil fuel use in Sweden. Today the Swedish electricity production is about 46% nuclear, 46% large hydro and the rest a mix of biofuel, waste and fossil fuel (the latter often imported).

Links to the previous posts in the series

[1] Often images gets pulled out of context, through Google Image Search for example, and then it is good to embed a bit more information in the image.

[2] Peat is counted as biofuel in Swedish energy balance calculations, but this is very doubtful as a practice, as it takes hundreds of years to regenerate. So on the time-scales of catastrophic climate change, it should really be classified as a fossil fuel.

Edit: Added link to previous post in the series.

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