An article in today’s paper suggested that South Australia would be powered by 100% renewable energy. As no time frame was given, this may be perfectly correct in some distant future. But what is meant by the statement and how do we perceive it?
First of all there is a vast difference between energy and electricity. A portion of our energy use, is in the manufacture of electricity while the rest is currently used for transport, manufacturing, steel, cement, aluminium production, cooking, heating etc. In the current world if oil is not a major component of the energy use story (ie transport) then the story is about electricity generation.
According to the Department of Industry and Science (2015) Australian Energy Statistics Electricity supply (from Power Stations) accounts for 27% of Australia’s energy use, transport is also about 27% and manufacturing and mining at 29%. Manufacturing can be broken down further to Ferrous metals 42%, non ferrous metals, 34%, chemicals 20%, Food, 13%, Petroleum refining 6%, Wood / paper 6% and Cement 5% (with a bit of rounding).
So, while we may be able to generate electricity for domestic and possibly commercial use using 100% renewables it is highly unlikely that we are anywhere near ready to supply all of our energy requirements. Steel manufacture, for example requires the use of coking coal.
This leads to a second problem with energy use accounting. Australia does little refining of petroleum products and yet uses large amounts of imported product. If we manufacture less we use less energy, shifting the issue elsewhere. Similarly if we manufacture in the suburbs, country towns and use the products in our cities can we really say that our cities use 100% renewables?
Australian Energy production by fuel type (not necessarily by Australian use) for 2013/4 was Coal 66%, Oil and Gas 18 %, Uranium 14% and renewables 2%.
Australian Electricity production
Electricity production in Australia (2013/4) is still predominantly from burning coal 61%, then gas and Oil at 24%, Hydro at 7% and Wind / Solar at 6%. Hydro is a special case ( only available to some) and will be dealt with in another blog.
It is difficult to obtain comparable numbers for comparable years, so all of these numbers are approximate. Domestic solar power use for example is largely an estimate. Australia is very good at producing well defined numbers for recent years in basic units (ie Joules) and making these available to the public. Using different units, publishing old statistics and mixing up electricity and energy statistics can make comparisons difficult.
South Australia does a brilliant job of publishing electricity statistics with a live update chart of Australian electricity generation by State and Source on the sa.gov.au site. It’s easy to see why as that state has up to 50% renewables use over the last 2 days with backup from gas ( the cleanest of fossil fuels with least greenhouse gas emitted. Tasmania also stands out with its reliance on hydro with backup from diesel generators (due to current problems with electricity imports).
It may also be noted that these states are the least prosperous with high electricity costs. Economics are not the purpose of this blog and I won’t go into details but the economics are probably more complex than the science when environmental aspects are included.
The charts also point to a third problem with energy accounting. Renewables vary significantly in their input into the electricity generation mix. Wind in particular is highly variable, with the generation slack taken up by gas ( in general). This is also supplemented by “cheap” coal power. Coal burners keep on burning whereas gas can be turned on or off. Imports and exports of clean energy versus “cheap” energy between the states complicate actual usage patterns (rather than generation. Base load requirements may mean that we use more coal fired power.
European Energy Use
Australia is an isolated island with a complex but well defined electricity mix. It is more complicated again to try to view the entire energy situation in Australia. When it comes to overseas usage, current, reliable information becomes more difficult to find. Hydroelectricity often distorts the world picture with statements like Norway (or other local areas) has near 100% renewable use when these are supplied by hydro.
Denmark is often touted as having the best energy policy in Europe (deserved or not?). The World Economic Forum suggests that in 2014 Denmark had the third best Energy Security in the world. This is partly due to their connectedness to Europe.
Electricity generation in Denmark in 2014 was 56% thermal (60% of this was coal) and 40 % wind. 33% of electricity generated was exported (mostly to Germany) and 36% was imported (mainly hydro and nuclear from Norway and Sweden). So Denmark does a great job on generating and using wind power but still uses coal for 34 % of electricity generation. The high levels of import / export are, I assume, to even out the uncertain level of wind energy generated (buffering). Denmark has no hydro and nuclear generation is banned.
Denmark generates some of the cheapest electricity in Europe, but with taxes added on, it has the highest electricity costs. About 10% of domestic energy consumption is from Nuclear power.
That’s the simple bit. Energy generation and use is another matter. In some ways Denmark is at the forefront of renewables. They have developed to geothermal district heating plants in Copenhagen and Thisted. This allows houses and community properties to be heated without the use of electricity or indeed, fossil fuels.
Denmark’s wealth over the last forty years has largely come from its oil discoveries in the North Sea. It is possible these will be expanded with ongoing exploration in Greenland and the Faroe islands. Denmark is a net exporter of oil.
Denmark’s energy use in 2015 is estimated at 37% oil, 18% coal, 18% gas and 27 % renewables (wind, geothermal, biofuels and imported hydro). You may find different figures here as different sites appear to publish different estimates. Denmark aims to have 30 % renewables by 2025 and be free of fossil fuel usage (not production!) by 2050. Their aim is to have battery operated vehicles by then.
World Energy Use
World energy use (in 2002) was estimated at 36% oil, 22% coal, 22% gas and 21% renewables / hydro / nuclear. It would appear to be a huge job to become 100% renewable in any near term.
Other major European countries have a similar mix. Germany in 2014 was about 35% Oil, 25% coal, 20 % gas, 20% nuclear and renewables. Germany is currently in the process of shutting its nuclear power stations and moving to renewables. This may mean more coal usage while it builds its renewables.
France is dominated by nuclear power with an energy mix of 43% Nuclear, 30% oil, 15% gas, 4% coal and 8% Renewable. A large amount of the nuclear generated electricity is exported making the usage mix at about 45% oil, 20% gas and 22% nuclear. Financially the nuclear industry is doing poorly in France. New plants are required but are now very high cost as is the problem of nuclear waste. Nuclear supplies base load electricity and is not easily shut off. This is a problem for adding wind and solar into the mix.
The US is about 37% oil, 24% gas, 22% coal, 10% nuclear and 7% renewable.
China is about 65% coal, 20% oil, 8% hydro, 5% gas and 2% nuclear and renewables, but is rapidly evolving.
It would appear to be a huge job to become 100% renewable in any near term. South Australia does a pretty good job!