I did not know that!
Looking out into Liverpool Bay from my home in North Wales, I can see several arrays of offshore wind turbines. I did not know that the latest turbines in the Burbo Bank Extension are so large, 82m long blades generating 8MW, that one rotation will power the average home for a whole day. And although I have been interested in sustainable agriculture and food production for a number of years, I didn’t appreciate that growing crops as an understory to forest trees could save 9.3 gigatons of CO2 by 2050, dramatically improve production efficiency, and generate an additional $710 billion in net profit at a cost of $27 billion investment.
I learned these and many other exciting ideas from Project Drawdown; a fascinating attempt to develop a route to reversing climate change.
During the recent Clean and Cool mission to San Francisco, we had an opportunity to hear about the project from the Research Director Chad Frischmann. Inspired, I bought a copy of the book as soon as I got back from the US. This is what I learned between Chad’s talk and the book.
“Drawdown is that point in time when the concentration of greenhouse gases in the atmosphere begins to decline on a year-to-year basis”
The problem with thinking about reversing climate change is the scale and complexity of the challenge. It is such a tangled, knotted and wicked problem that people are overwhelmed and see no way forward. The language of debate is full of doom and gloom and there seems little prospect of success. Project Drawdown seeks to reframe the discussion by showing that there are economically and technically viable solutions in our hands that together can address the problem. Acceleration is needed rather than invention.
They define drawdown as “… that point in time when the concentration of greenhouse gases in the atmosphere begins to decline on a year-to-year basis”, and the target is to achieve this critical inflection point by 2050.
65 researchers supported by 130 specialist advisers looked at all the evidence on technologies and practices which could reduce greenhouse gases. They whittled the list down to 80 established solutions that are economically viable and scalable, and 20 emerging solutions that they called “coming attractions”. These were tested in a global systems model that allows the impact of any technology or practice to be evaluated.
In trying to find practical solutions to climate change, Project Drawdown builds on earlier ideas such as the Seven Stabilisation Wedges. The difference here is that Drawdown is both more granular, covering a lot more potential solutions, and more detailed, giving much better information on the likely impact of each solution. Their global systems models allow them to look at the interdependencies between solutions, and to avoid double counting.
What solutions do we have right now for climate change?
Getting into the meat of the project, the solutions are grouped into eight categories:
- Energy
- Food
- Women and Girls
- Buildings and Cities
- Land Use
- Transport
- Materials
- Coming Attractions
Each of the 80 established solutions is ranked according to how many gigatons CO2(eq) could be reduced by 2050, what would be the net cost of implementation, and any associated savings. There is also a description of the solution and examples of its use. Each of the coming attractions is given a description of the current state-of-the-art, and what we might hope for in the future.
Project Drawdown goes further by evaluating each solution under three scenarios:
- Plausible – based on existing rates of adoption for the solution
- Drawdown – driving the rate of adoption through policy and financial incentives to reach the inflection point by 2050
- Optimal – completely replacing all existing solutions by superior alternatives by 2050
Under the plausible scenario the 80 validated solutions would reduce CO2(eq) by 1,051 gigatons by 2050. Substantial, but it doesn’t start to see CO2(eq) in the atmosphere coming down. The drawdown scenario would see a reduction of 1,442 gigatons by 2050 with a net reduction of 0.59 gigatons per annum from then on. The optimal scenario could reduce CO2(eq) by 1,613 gigatons by 2050, and would potentially allow us to reach drawdown as early as 2045.
Well that’s a surprise!
The top 15 solutions under the plausible scenario are shown in the table. There are some surprising items on the list, and some surprising omissions. Nine of the top 15 relate to food, agriculture and land use. There is enormous potential to avoid carbon emissions by a more efficient food supply chain, and by taking advantage of the carbon sequestration capabilities of the biosphere through careful use of land.
| Solution | Ranking | Gigaton Reduction |
| Refrigerant Management | 1 | 89.74 |
| Onshore Wind Turbines | 2 | 84.60 |
| Reduced Food Waste | 3 | 70.53 |
| Plant-Rich Diet | 4 | 66.11 |
| Tropical Forests | 5 | 61.23 |
| Educating Girls | 6 | 59.60 |
| Family Planning | 7 | 59.60 |
| Solar Farms | 8 | 36.90 |
| Silvopasture | 9 | 31.19 |
| Rooftop Solar | 10 | 24.60 |
| Regenerative Agriculture | 11 | 23.15 |
| Temperate Forests | 12 | 22.61 |
| Peatlands | 13 | 21.57 |
| Tropical Staple Trees | 14 | 20.19 |
| Afforestation | 15 | 18.06 |
The impact of educating girls and providing widespread access to contraception is a reduction in the number of children born. Not through coercion, but through a wider range of choices. Social changes like this, and a move to a more plant rich diet, look more complex than some of the technological fixes, but social shifts are an essential part of the transition to a sustainable future.
Solutions directed at buildings and cities don’t appear at all in the top 15. A personal disappointment since I have spent so much time over the last 10 years trying to make buildings and cities more sustainable. But just looking at the numbers I can see that there are other solutions with a much bigger potential, and I can console myself that we still need all the solutions to reach drawdown.
“…the biggest single thing we could do to reduce CO2(eq) in the atmosphere is to manage refrigerant chemicals more effectively”
And perhaps most surprising of all, right up there at number one, the biggest single thing we could do to reduce CO2(eq) in the atmosphere is to manage refrigerant chemicals more effectively. The reason it is such a problem is that current refrigerants have a global warming potential that is 1000 to 9000 times greater than CO2, and as the world develops the number of refrigeration and air-conditioning units in use grows constantly. We need to prevent their release during manufacture and use, and destroy them at the end of life. Achieving that is the objective of the Kigali amendment to the Montréal Protocol signed in 2016.
Read this book!
The book is 240 pages of detailed analysis and fascinating insight. It pulls together 100 possible solutions to climate change and what they might be worth. Project Drawdown plans to publish all of its models and raw data on their website to allow everyone to see what is going on and to test out their own ideas and combinations of solutions.
Read this book. Argue with its conclusions. Write to the research team to tell them where they got it wrong. Develop ideas for innovation and implementation. Scribble all over it. Throw it against the wall in a fury. But whatever you do, don’t ignore it. We need solutions to climate change, and I have seen no better resource on the most feasible solutions with our current state of knowledge.