Every six or seven years, the Intergovernmental Panel on Climate Change (IPCC) releases a comprehensive report assessing evolving knowledge about climate change, its causes and impacts, and—more importantly—what we can do about it. The fifth report was released in 2014 and the sixth report was just released in April of 2022.
The 2022 report is a mix of good and bad news. It primarily uses data from the last decade (2010-2019) to illustrate global changes. The bad news: total net anthropogenic emissions have continued to rise along with cumulative emissions since 1850. The good news: the rate of growth from 2010-2019 was lower than in the previous decade (2000-2009). This is illustrated in the chart below.
However, despite the report’s good news, this doesn’t necessarily mean the growth rate will continue to decline, and a lot of work still needs to be done, and fast. The report urges with “high confidence” that the continued installation of unabated fossil fuel infrastructure will ‘lock in’ GHG emissions.” This means that if immediate action isn’t taken between now and 2025, the Earth will experience a warming of 3.2 degrees C by 2100, even if we attempt corrective action.
A huge inhibitor of climate change abatement is money. Manufacturers won’t choose sustainable materials if they cost more than petroleum-based products. The average apartment complex won’t shell out thousands of dollars to purchase energy-efficient light bulbs. Despite the natural aversion to spending money, these are changes that need to be made. This year’s report outlines the costs of various changes for each of the five main sectors: energy, industry, buildings, transport, and AFLOU (agriculture, forestry and other land use). In the following sections, we’ll explore which changes are cheap enough for businesses and government to make right now.
- Energy (C.4)
The cheapest and most impactful changes in any industry occur in the energy sector. Between 2010 and 2019, unit prices for solar energy fell by 85%, wind energy fell by 55%, and lithium-ion batteries fell by 85%. There was also a substantial increase in use with 10x deployment for solar energy and more than 100x for electric vehicles. The prices and adoption levels for major renewable alternatives are shown below.
These statistics vary by region and are unfortunately lower in developing countries due to weaker enabling conditions and lack of digitalization. However, wind and solar energy are both projected to reduce net emissions by more than 2 gigatons of CO2 per year while costing less to implement than the current fossil fuel systems. This reduction is more than the reductions of hydropower, geothermal energy, and nuclear energy combined.
- Industry (C.5)
Because the industry sector is one of the biggest emitters of greenhouse gasses, it’s also the most expensive to reform. The largest reduction for industry comes from fuel switching, which means exactly what it sounds like: switching to more sustainable fuel sources than fossil fuels, such as natural gas, bio-energy, and hydrogen. This change would reduce emissions by just over 2 gigatons of CO2 per year, but it would also cost 100-200 USD/ton. The next highest reduction in CO2 emissions from industry is also the cheapest, and we’ve discussed it already: energy efficiency. Using energy-efficient technology in industry would cost 0-20 USD/ton and reduce emissions by about 1.25 gigatons of CO2 per year. Overall, changes in industry will be hard to implement because they’re so expensive.
- Buildings (C.6)
Like the transport sector, the buildings sector has a number of cheap and impactful changes. Increasing efficient lighting, appliances, and equipment has a lower cost than the current systems while reducing emissions by about 1 gigaton of CO2 per year. Bottom-up studies claim that 61% of global building emissions could be mitigated with sufficient policies. Sustainable building construction and certification programs (such as LEED) have become popular in recent years, and universities across the United States have taken the lead (no pun intended) on green buildings. There is a high potential in developing nations for ground-up net-zero building, while in developed countries, retrofitting will need to become a priority.
- Transport (C.8)
The energy supply and industry sectors saw a slowing GHG growth rate between 2010-2019 compared to the previous decades. The transport sector, however, held steady at a growth rate of 2%, and in 2019, transportation accounted for 15% of all anthropogenic GHG emissions. This is easily preventable, as the transportation sector is full of small yet cheap ways to reduce carbon emissions. Many of the reductions hinge on energy efficiency: getting more bang for our buck. This includes fuel-efficient light and heavy-duty vehicles, optimization of shipping, and energy-efficient aviation. All of these changes reduce emissions by less than 1 gigaton of CO2 per year, but they cost less than the current systems. Other cheaper changes include cutting down on personal energy use by shifting to public transportation and bikes/e-bikes. The most expensive transition in the transport sector is biofuels, with a predicted reduction of about 1 gigaton of CO2 per year at a cost of 50-100 USD/ton.
- AFLOU (Agriculture, Forestry, and Other Land Use) (C.9)
Similar to the industry sector, the agriculture and forestry sector has high but expensive mitigation options because it’s something humanity relies on so extensively. The highest reduction in the agriculture sector has a similar impact to solar and wind power, and involves the reduced conversion of forests and other ecosystems. Trees draw in carbon dioxide for photosynthesis and release oxygen, regulating the greenhouse gas balance in our atmosphere. It seems like leaving trees alone wouldn’t cost too much, but this change is projected to cost around 50-100 USD/ton to reduce CO2 emissions by 2 gigatons per year.

Conclusion
This IPCC report has some encouraging and not-so-encouraging statistics. Nevertheless, action needs to be taken now—the question is, which actions? It’s likely that businesses and the government, as well as individuals like me and you, will want to choose the options that cost the least. Luckily, this report indicates that cheap options do exist. In the United States, renewable energy presents the biggest opportunity. Switching to wind and solar is a viable option, and that’s something you can do, too. After renewables, it’s all about energy efficiency. Try switching out your lightbulbs for more energy-efficient versions, or hop on the bus instead of driving to work. Keep an eye on your local ballots to see which politicians are advocating for the changes in the chart above. Climate change might feel out of your hands, but this report shows that positive change is possible.
There are affordable tactics that can be immediately deployed in the United States and elsewhere, but do you think we can make these changes happen on a nationwide scale?