IELTS writing task 1

The four pie charts depict the production of electricity in Australia and France in two different years: 1980 and 2000.
Overall, it can be seen that the total production of electricity increased for both countries: in Australia from 100 units in 1980 to 170 units in 2000, whilst in France from 90 units in 1980 to 180 units in 2000, exceeding the Australian production.

To begin with, in 1980, in Australia half of the electricity production in Australia was due to from coal sources, whereas in France this amounted to 25 units. (are the half and the 25 units directly comparable? Given that the pie charts represent different totals they cannot be compared in this way as the 25 units on France is 25/90 not 25/100. I would suggest you use the same units for both, namely half and just over a quarter or use percentages. I would suggest you choose and stick to it for all the others in that follow below too, just so the statistcs aren't confusing or misleading) In Australia, natural gas and hydro power both produced 20 units each (20%), while the remaining 10 units (%) were due to oil sources. In France, natural gas and hydro power made up 25 units and 5 units respectively (or 1/3 together), whilst oil and nuclear power contributed to producing 20 units and 15 units respectively.

In 2000 there was a massive change for both countries regarding the use of sources used for producing electricity.
In Australia 130 units were obtained from coal power. whereas hydro power, natural gas and oil produced made up only 36,2 and 2 units respectively. 25 percent collectively.
In France, the main source was nuclear power making of 126 units (almost 75%). Coal power production remained the same at 25 units (but this now represents a smaller share of the total), while oil increased the production to 25 units (however, this is actually a decrease in its overall contribution to electricity production because 20/90 is much bigger than 25/180). Hydro power and Natural gas contribution both decreased to only 2 units each.

You might want to finish with a couple of lines to conclude as it just feels like you've stopped very abruptly and forgotten to finish. You're English is actually very good, just a shame they've given you pie charts that are not as easily comparable as they appear.