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While predicting the climate is hard, predicting humans is even harder. The notion that we are inevitably on the way to 4C of warming (or whatever other figure

While predicting the climate is hard, predicting humans is even harder. The notion that we are inevitably on the way to 4C of warming (or whatever other figure somebody would have you believe) is frankly outright wrong. We can reach net zero greenhouse gas emissions through profitable enterprise and without lowering quality of life / stopping economic growth / enforcing strict veganism or whatever else extremists propose. In fact, we can do so far ahead of the IPCC SR15 1.5C scenario requirements. How? Firstly, don't disregard technologies without understanding their merit. Hydrocarbons are a big part of the problem, yes, but please note that natural gas is about 4x cleaner than coal and has actually been the largest contribution to lowering emissions in the energy sector (~75% natural gas reduction on a large chunk of energy consumption is far more significant than the ~95% renewable reduction on a much smaller portion of energy consumption thus far) Our world relies on these technologies at the moment and a good climate change solution must include not only a smooth transition away from fossil fuels but also an increase in fossil fuel cleanliness. Now, climate change is primarily driven by net emissions from 6 things: - Energy (electricity, fuels, heat etc.) - Transportation (cars, planes, boats etc.) - Industry (steel, concrete, plastic etc.) - Commercial (buildings, appliances, etc.) - Agriculture (mostly beef, other meats, etc.) - Carbon sequestration (deforestation, other tech) Here's how we can solve the problem in all of these areas in a mutually beneficial, profitable way: 1. Nuclear fission is currently the cleanest, safest, and most fuel abundant energy source we have. Most people don't know this. It is also only at a very small fraction of its potential in efficiency and relies on the least common nuclear fuel of the 3 naturally occurring isotopes (U235 vs. Th232, U238) With some relatively small investment in this space, we can both increase the world's total energy supply by several factors in order to accommodate growth in developing nations and decrease energy sector emissions by >99%, over the course of a few decades. We can also provide enough cheap electricity to help with the other 5 areas: 2. Electric cars are physically more efficient, faster, and simpler than ICE cars. Same concept applies long term to all transport with the exception of orbital rockets (those which operate in a vacuum), and it is entirely possible that we can shift the entire transportation industry to a mix of (a) fully electric transport and (b) carbon-neutral fuels derived from sequestration techniques, all within a few decades. 3. High grade heat allows us to shift the emissions of steel manufacturing from the plant itself to the energy source. New nuclear fission technologies operating >600 degrees Celsius will allow us to shift the steel industry to net-zero emissions. Bill Gates recently also posted some notes about green concrete https://www.gatesnotes.com/Energy/Buildings-are-good-for-people-and-bad-for-the-climate https://www.gatesnotes.com/Energy/Buildings-are-good-for-peo... Also, cross laminated timber offers a new technology that can be made stronger, cheaper, safer, and more psychologically beneficial than steel and concrete in most buildings, including skyscrapers. This and other biological materials science solutions can help shift away from steel, concrete, and plastic production. 4. Same concept from transportation applies here. Electric things are more efficient and will be cheaper long term across the board, and allow us to shift emissions to the energy sector (which is by far the easiest to reduce emissions in) 5. Agriculture is complicated, and feeding 10 billion people will be hard. But there are a lot of great options and innovations here as well. Indoor farming can be made significantly more reliable, productive, and efficient than regular farming if we have good access to electricity and water. Lab-grown meats, cultural shifts to vegetarianism/veganism, and alternative protein sources all offer options to reduce agricultural emissions by >95%. 6. There are many great companies working on sequestration technologies, and several of these not only remove greenhouse gas from the atmosphere but also provide useful byproducts like clean hydrocarbon fuels. YC has recently funded such companies. The technological shifts I proposed in sections 4 and 5 will allow us (and/or force us) to start fixing our land and replanting healthy forests. Every single one of these solutions can realistically be widely implemented by the year 2040/2050, and if we really wanted to (although this is not realistic from a societal perspective) we could really get there by 2030. Every single one of these solutions can improve quality of life and support a growing global economy in a profitable way. I believe we are going to reach net-zero emissions a lot faster than you might expect. Please, don't fall for the fear mongering. (and obviously, also don't fall for denialism) Climate change is real, but it is something we can solve, and we don't have to destroy society or adopt a political extreme across the board to do it. I've got hope for humanity, I hope you do too.

jeffreyrogers 7y ago
I think you've pointed out reasons to be optimistic, but these problems are harder than you're implying, even assuming we have the political will and foresight to address them. For example, electric cars require large amounts of copper, cobalt, and nickel. We don't produce enough to electrify all cars, so that means we need new mines. Mines take a long time to discover and build and have their own environmental problems. Also, recyclability of these batteries still needs a lot of work. As for shifting steel to net-zero emissions, I agree it's possible in principle, but you need to get a lot hotter than 600C. Steel melts at ~1500C. A blast furnace needs to get to at least 1300C to separate iron from ore and temperatures can get up to ~2000C. The engineered wood products are interesting, but they aren't well understood yet for use in large structures. One of the advantages of reinforced concrete is that the building is monolithic. There are no joints that can fail, it's one piece of reinforced concrete. The composites need joints, and every joint is a potential source of failure, which can then load other joints, potentially causing them to fail, and so on. These probably aren't insurmountable problems, but they are unsolved engineering problems and create a more complex structure. I'm not trying to be pessimistic or contrarian. I think technological advances will be important in maintaining quality of life as we transition to more sustainable sources of energy, but they aren't going to solve all our problems.
- WorldMaker 7y ago
  > For example, electric cars require large amounts of copper, cobalt, and nickel. We don't produce enough to electrify all cars, so that means we need new mines. Cobalt comes "free" as a waste product from copper/nickel mining. So long as copper/nickel get mined, there will be cobalt. There doesn't currently seem to be any threat right now of a shortage in the cobalt market (even in some hypothetical of "electrify all cars immediately" worst case). On top of that, we already have proven Lithium Ion battery formulations that don't need Cobalt (it's about a quarter of batteries on the market), and the ones in current production that use Cobalt typically list their usage of Cobalt in ppm [parts per million]. > Also, recyclability of these batteries still needs a lot of work. Current car-sized batteries have been showing real world usage statistics at hundreds of thousands to just shy of tens of millions of cycles in their "first use" in cars, not enough have made it to secondary markets yet to have reliable statistics, but current beliefs are that secondary usages in devices such as "power walls" and grid supplementations should see tens of thousands of cycles at reduced capacities. In the tertiary stages where recycling becomes useful/necessary, we know that Lithium, the vast majority of battery compositions, is entirely recyclable (and a known entity, we've doing that much for a while). We aren't currently good at recycling Cobalt, but we haven't needed to do any such thing in bulk to date because A) again, most car batteries are still in their first lives, which are showing to be 15-20 years in some cases, B) Cobalt is often measured in ppm so a tiny percentage of battery composition, C) Cobalt is a "waste product" from other mining and economically the incentives just do not align to recycle it when it just keeps coming out of mines whether or not we need it. Not that pessimism isn't useful, but another possibly helpful reminder we may be better off than we think we are.

jeffreyrogers 7y ago

I think you've pointed out reasons to be optimistic, but these problems are harder than you're implying, even assuming we have the political will and foresight to address them. For example, electric cars require large amounts of copper, cobalt, and nickel. We don't produce enough to electrify all cars, so that means we need new mines. Mines take a long time to discover and build and have their own environmental problems. Also, recyclability of these batteries still needs a lot of work. As for shifting steel to net-zero emissions, I agree it's possible in principle, but you need to get a lot hotter than 600C. Steel melts at ~1500C. A blast furnace needs to get to at least 1300C to separate iron from ore and temperatures can get up to ~2000C. The engineered wood products are interesting, but they aren't well understood yet for use in large structures. One of the advantages of reinforced concrete is that the building is monolithic. There are no joints that can fail, it's one piece of reinforced concrete. The composites need joints, and every joint is a potential source of failure, which can then load other joints, potentially causing them to fail, and so on. These probably aren't insurmountable problems, but they are unsolved engineering problems and create a more complex structure. I'm not trying to be pessimistic or contrarian. I think technological advances will be important in maintaining quality of life as we transition to more sustainable sources of energy, but they aren't going to solve all our problems.

WorldMaker 7y ago
> For example, electric cars require large amounts of copper, cobalt, and nickel. We don't produce enough to electrify all cars, so that means we need new mines. Cobalt comes "free" as a waste product from copper/nickel mining. So long as copper/nickel get mined, there will be cobalt. There doesn't currently seem to be any threat right now of a shortage in the cobalt market (even in some hypothetical of "electrify all cars immediately" worst case). On top of that, we already have proven Lithium Ion battery formulations that don't need Cobalt (it's about a quarter of batteries on the market), and the ones in current production that use Cobalt typically list their usage of Cobalt in ppm [parts per million]. > Also, recyclability of these batteries still needs a lot of work. Current car-sized batteries have been showing real world usage statistics at hundreds of thousands to just shy of tens of millions of cycles in their "first use" in cars, not enough have made it to secondary markets yet to have reliable statistics, but current beliefs are that secondary usages in devices such as "power walls" and grid supplementations should see tens of thousands of cycles at reduced capacities. In the tertiary stages where recycling becomes useful/necessary, we know that Lithium, the vast majority of battery compositions, is entirely recyclable (and a known entity, we've doing that much for a while). We aren't currently good at recycling Cobalt, but we haven't needed to do any such thing in bulk to date because A) again, most car batteries are still in their first lives, which are showing to be 15-20 years in some cases, B) Cobalt is often measured in ppm so a tiny percentage of battery composition, C) Cobalt is a "waste product" from other mining and economically the incentives just do not align to recycle it when it just keeps coming out of mines whether or not we need it. Not that pessimism isn't useful, but another possibly helpful reminder we may be better off than we think we are.