Posted: 4 April 2021
4th April 2021. First book of the year! I’ve been slowly working my way through the Japanese Economy textbook. I should be done with that by H2 2021. I’ve always been a fan of GatesNotes and of course Bill Gates himself, so it’s natural that when this book was released, I immediately ordered it and finished it quickly.
In this book, Gates broke down all global emissions into five major components. How we make things (31%), make electricity (27%), grow things (19%), get around (16%), keep cool and stay warm (7%). EVs aren’t the moonshot solution if the electron used to move that EV is a dirty electron. At the end of the day, we need to fix “making electricity”. That’s a really hard problem, as storage and distribution is even harder. The technology to make clean energy already exists.
Let’s use Singapore as an example. For Singapore to be 100% solar sufficient, we need to generate 200% worth of energy in a day. The first 100% assumes that energy is generated from 7am to 7pm when the Sun is up. The second 100% needs to be generated during the same period, stored, and then consumed at night. This of course simplifies the whole situation a lot, as there’s cloud cover, rain, the Sun moving throughout the day, etc. In 2019, Singapore consumed 51.7TWh (see EMA website). From NASA’s site, we can see that 1360W per square meter of energy reaches the top of atmosphere, if it’s directly facing the Sun. For ease of calculation, we will just assume that 1000W hits the Earth’s surface, a gross overestimation. If we assume 20% efficiency for solar panels (most commercial ones hit around 20%), and 12 hours of “full sunlight”, then a square meter in Singapore can generate 2.4KWh. 51.7 TWh translates to 141GWh in a day and 11.75GWh in an hour. This translates to 4.8 million square meters, An area about 2Km by 2Km. Hmmm… This is extremely back of the envelope and I hope I’m getting the interpretation of watts correctly. Let me know if I am not! I cross checked with this article and it seems to make sense. From this perspective, it does seem that Singapore can truly be 100% solar self sufficient…? If we could install battery technology in each HDB, and have central cooling systems, that might be very interesting. As stated above, the generation part is very feasible - the technology exists and it’s about scaling up. The storage part is really hard. Gates mentioned a hypothetical scenario about a three day power outage in Tokyo. If Tokyo was fully running on clean energy and has long term battery technology in place, then it would need more than 14 million batteries just for these three days - more storage capacity than the world produces in a decade. Averaged over the lifetime of the batteries, that’s an expense of 27 billion (data here cited from Gates’ book). I can’t say this enough because I keep coming back to this - storage and distribution is REALLY hard.
Gates talked about fertilizers as well, something of interest to me recently. Microorganisms in the soil that make nitrogen expend a lot of energy in the process of making nitrogen. They have evolved to only produce nitrogen when they absolutely need to, when there’s no nitrogen in the soil around them. This is why synthetic fertilizers disrupt the natural ecosystem in the soil. I’ve not used synthetic fertilizers in my garden and my plants are thriving. Gates also introduced CGIAR, the world’s largest agricultural research group, and the various alphabet soup organizations related to CGIAR. This is the first time I’ve heard of this. Last but not least, I learnt about Scuba Rice - that’s super cool.
Climate change involves more than just technology. Politics matter at the end of the day because the party that wants to increase prices of gasoline and food for the masses will not get voted in. However, the politicians can still play a part in crafting policy that encourages industry to go green. Everyone has to play a part in perhaps this greatest challenge of my generation (?).