Carbon intensity of 85 countries
Interested in the data that went into the infographic above? We discuss here the country with the cleanest energy. Before we had written about electricity-related emissions for a select group of countries around the world. Here we discuss a really broad swathe of countries, 85 in total. We also generalize the analysis beyond electricity. Using a BP report on energy usage in 85 countries, we computed the carbon intensity for each. The carbon intensity of energy means here, the amount of carbon emitted per unit of energy used. To calculate the carbon intensity, we divide the carbon produced (in grams) by the total energy produced in the country (in kWh). The resulting units of comparison are grams of CO2 per kWh of energy.
Country with the cleanest energy: Iceland at top of rankings, South Africa at the bottom
With no greater context, we see that Iceland has the cleanest energy generating only 31 g CO2/kWh. Close behind are the Scandinavian countries. Norway has the second cleanest energy at 58.9 g CO2/kWh, and Sweden has the third cleanest energy producing 63.3 g CO2/kWh. In contrast, we see that South Africa has the highest carbon emissions per unit energy at 318.2 g CO2/kWh, followed by Kazakhstan with the second highest carbon emissions per unit energy at 278 g CO2/kWh, and Estonia with the third highest carbon emissions per unit energy at 273 g CO2/kWh.
The global average is 190 g CO2/kWh. Remarkably this is 6 times higher than Iceland.
Computing impact by considering the total energy produced
Countries have little impact on global emissions even if they have very clean energy but produce little of it. That is because if they are very small, then the carbon reduction is also small. Instead of calculating the carbon intensity, we plot out separately the carbon emissions (megatons) vs the total energy produced (exajoules). Below is a plot of the carbon emissions vs. the total energy production. This has the same information as in the above chart except we break out the two numbers.
A trend line of emissions vs energy accounts for the size of a country’s energy production
The chart of emissions vs energy produced shows each country as a dot. In fact these countries lie along a “trend line”. The trend line is like an “average” of emissions vs energy. If you’re above the line, then you have more emissions than expected based on the trend of all countries. Similarly if you’re below, you have fewer emissions that expected by looking at all countries. Note that a lot of countries are in the lower left and we see only 5 countries clearly. Let’s take a look.
Big energy producers means big impact on carbon emissions
First, we look at the big producers to the upper right. China and India are above the trend line whereas the US is slightly below. This means that China and India emitting more than expected for countries of their size, and the US emitting less than expected. For China we estimate by eye that it could reduce emissions by 1000-1500 megatons of carbon per year if it changed up its sources. India could reduce its emissions about 500 megatons. Because these three countries are on the far right edge of the trendline, all have enormous impact. Meaning, a 1% change in carbon emissions equals about 100 megatons of carbon change for China, 47 megaton change for US, and 25 megaton change for India.
Top 10 energy producers: Brazil is the country with the cleanest energy
It’s hard to see the top 10 energy producers because the countries get bunched up. I list them here in order: China, US, India, Russian Federation, Japan, Canada, Germany, South Korea, Brazil, Iran. Among these China has a carbon intensity of 240 g CO2 / kWh and the US has a carbon intensity of 182 g CO2 / kWh. You may think oh yes the US is much cleaner. But going a bit further down the list we find that Brazil’s carbon intensity is the lowest of the big energy producers at 125 g CO2 / kWh. So among the top 10 energy producers, Brazil is the country with the cleanest energy.
The reason is that Brazil uses a lot of hydro power and biofuels and natural gas. Hydro power inherently is a low emissions source. Biofuel burning generates carbon but in principle that’s recaptured by the raising of crops. Natural gas is one of the cleaner burning fuels. The rest is oil. Although Brazil’s share of oil burning isn’t much different from countries like the US, the other low carbon sources push its carbon intensity quite low.
Smaller energy producers require a logarithmic view
There are a whole lot of countries on the far left lower corner. To see these, we expand the axes of the plot by using logarithmic scale. In a logarithmic scale, a unit change is 10 times larger or smaller in each direction. This is like the Richter scale for earthquakes. Every point change means an exponential change. Below, in the new chart, we see Iceland now surprisingly falls far below the trend line. But you can also see now that Iceland’s energy impact is less than Sweden and Norway. Iceland produces very little energy, about 10 times less, than the Nordic counterparts.
Iceland, the country with the cleanest energy and South Africa, the country with the least clean energy
Is this surprising? We find that Iceland is reported to be powered by 85% geothermal energy making its share of renewables very high among all countries. Whereas for South Africa, the BP energy study reports that 72% of kWh generated is from coal. This makes South Africa heavily dependent on a cheap but very carbon intensive fuel. South Africa’s
Iceland’s use of renewables has increased over the last 30 years (below). The renewables are not only geothermal, but include hydro power as well. Coal is a steady small fraction and oil is the fossil fuel that has declined by more than half since 1990s. Iceland’s ability to keep the carbon emissions extraordinarily low using geothermal is not going to work for other countries. Most countries aren’t densely dotted with springs and volcanoes. However, countries like Sweden, Norway, and even Trinidad Tobago, that use a mix of natural gas, nuclear power, hydro power, and wind, are great examples to study and follow.
South Africa on the other hand remains highly dependent on coal, which has remained unchanged over 30 years. Below we see a chart that in fact oil’s share of energy consumption has grown. Biofuels are a type of renewable in the sense that the crop absorbs carbon which are deposited back into the atmosphere after burning. However, dependency on biofuels has decreased. Certainly there’s much to be gained in switching to new carbon efficient sources.
So which country has the cleanest energy? Out of all of them, Iceland has the cleanest energy. Because its a small country, we consider separately the country with cleanest energy among the top 10 energy producers. That would be Brazil. Brazil is the country with the cleanest energy among the top 10 energy producers. Which country has the least clean energy? South Africa has the least clean energy. Similarly, a different country emerges if we consider among the top 10 energy producers. India is the country with the least clean energy among the top 10 energy producers.
Anna Lauer is a writer, gardener, and homesteader living in rural Wisconsin. She has written for Mother Earth News, Grit, and Hobby Farms magazines. Anna is writing a new book about growing your food for free and an ultimate guide to producing food at little to no cost. When she’s not writing or gardening, Anna enjoys spending time with her husband and two young daughters.