June 13, 2024
One of the most transformative changes in technology over the last few decades has been the massive drop in the cost of clean energy. Solar photovoltaic costs have fallen by 90% in the last decade, onshore wind by 70%, and batteries by more than 90%.
These technologies have followed a “learning curve” called Wright’s Law. This states that the cost of technology falls consistently as the cumulative production of that technology increases.
The chart shows the perfect example of this for solar power. This data comes from the International Renewable Agency, Greg Nemet, and Doyne Farmer & François Lafond.
On the horizontal axis, we have the cumulative installed capacity of solar panels, and on the vertical axis, the cost. Both are measured on logarithmic scales, and the trend follows a straight line. That means the fall in cost has been exponential.
Costs have fallen by around 20% every time the global cumulative capacity doubles. Over four decades, solar power has transformed from one of the most expensive electricity sources to the cheapest in many countries.
Technologies that follow Wright’s Law get cheaper at a consistent rate, as the cumulative production of that technology increases.
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November 22
Around 90% of the world’s carbon dioxide (CO2) emissions come from fossil fuels and industrial processes such as cement production. The other 10% comes from land use change, primarily carbon released from trees and vegetation due to deforestation.
Fossil fuels are also the biggest source of emissions at the national level in most countries across the world. But there are a few exceptions.
In the chart, you can see the share of emissions from fossil fuels compared to land use change across a small selection of countries. In the United States, the United Kingdom, and China, fossil fuels dominate. This data comes from the Global Carbon Project.
However, in Brazil, land use change plays a much more significant role. This is for two reasons. First, deforestation rates are higher than in most other countries. Second, Brazil has a very clean power grid. Most of its electricity comes from hydropower, with solar and wind also growing quickly. It burns very little coal and gas.
Explore data on how emissions compare across the world and by source →
November 21
The United States is the world’s largest oil producer.
The chart shows annual production by country from 1990 to 2023. The US has been the largest producer for the last seven years.
Production in the US gradually declined during the 1990s and early 2000s but increased steeply again post-2010 and is now at an all-time high.
This data comes from the Energy Institute’s Statistical Review of World Energy.
Explore oil production data for more countries and further back in time →
November 20
European neighbors Portugal and Spain are currently neck-and-neck in the race to roll out solar and wind power.
On the chart, you can see the share of electricity from the combination of solar and wind in each country. Their rate of progress has been very similar.
In 2023, both countries generated around 40% of their electricity from these sources. Wind power is more prevalent in Portugal, while solar is more used in Spain.
This data comes from Ember.
Explore more data on the rollout of clean energy across the world →
November 19
There are two key drivers of sea level rise. First, water expands as it gets warmer. Second, ice on land — in the form of ice sheets and glaciers — melts and adds water to ocean basins.
Both of these processes have accelerated due to climate change. The effect is shown in the chart, based on data from the US’s National Oceanic and Atmospheric Administration. It combines two sources: recent data from the University of Hawaii Sea Level Center and a publication from Church and White (2011).
On this chart, the rise in sea level is measured relative to the average from 1993 to 2008. Levels had risen by almost 20 centimeters between 1880 and this period, and 5 more centimeters since. Combined, that’s around 25 centimeters.
Explore more data on the impacts of climate change →
November 18
Food miles — moving products from farms to processors to consumers — contribute just 5% to 6% of the greenhouse gas emissions from food. Instead, most emissions come from land use change or emissions on the farm.
Within food miles, people often assume that international freight accounts for most of the climate impact. In reality, most of these emissions come from domestic delivery trucks on the road.
In the chart, you can see the breakdown of transport’s 5% of food emissions. Road transport represents 3.9%, compared to just 0.02% from aviation. This is based on data from a 2021 study by researchers M. Crippa and colleagues.
International food miles are just a small share of emissions because very little food is flown by air, and transporting goods by boat is much more carbon-efficient than by road.
Read more about the impact of food miles →
November 15
Today, there are around 830 million people aged 65 and older in the world. According to the latest UN data, it is projected to grow to 1.7 billion by 2054.
Asia, the world's most populous continent, is at the heart of this change, with its elderly population expected to more than double.
While rapid population growth has driven some of this increase, better healthcare and longer life spans also play a huge role.
It’s a great achievement that so many more people are living longer, healthier lives. At the same time, the working-age population will only grow 20% between 2024 and 2054. Societies will need to figure out how to care for more elderly people while improving everyone’s quality of life.
Explore population growth across countries with our explorer →
November 14
Around 40% of the world’s plastic waste comes from packaging. Packaging also makes up a significant share in the three regions that generate the most plastic waste: the United States, Europe, and China.
Packaging accounts for 37% of total plastic waste in the United States. It’s 38% in Europe, and in China, it's 45%. Together, these regions account for 60% of global packaging waste generation. This data comes from the OECD Global Plastics Outlook.
These figures show the vast impact of packaging on global plastic waste.
Explore how other sectors contribute to plastic waste production →
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