Why Zero
- Global average temperature have +1 degree Celsius since industrial age; a little is a lot, Ice Age –6, dinosaurs age where crocodiles at arctics +4; on current trend, +3 by midcentury, +4 to 8 by 2100
- Effects we are seeing: increased rainfall near oceans (as water evaporates) and droughts on land (as soil loses water); more wildfires; rising sea level (heat expands seawater + polar ice melting); decreased biodiversity etc
- 51bn tons world annual emission of CO2 equivalent, 37bn CO2, 10bn carbon; on current trend, +50% by 2050
This Will Be Hard
- Urbanization. World's building stock (number of buildings and their sizes) to double by 2060; every month a NYC for 40 years; people's living condition will continue to improve and energy consumption per capita will increase
- Energy industry inertia. Fossil fuel has become an extraordinarily efficient power source (high power density, affordability, reliability); from investment POV, large capital outlay, long investment cycle, existing infrastructure; absence of Moore's law (exponential progress) in energy technology eg cars and soalr panels
- Lack of global consensus. Two alternative narratives: 1) climate investments to make ways for healthcare & education; 2) we have all we need (EV, solar panels), just need to deploy them, no need to invest in breakthrough technologies; Paris agreement target reduction of 12% by 2030, not ambitious goal but showing global cooperation is possible
Framework to Evaluate Climate Ideas
- Which area of emission is targeted (area – CO2 share)? And how much % of 51bn tons are you aiming to reduce?
- Making Things (cement, steel, plastic production) 31%
- Plugging in (electricity generation) 27%
- Growing Things (agriculture) 19%
- Transportation (planes, trucks, cargo) 16%
- Temperature control (heating, cooling) 7%
- If it's electricity generation, how much watts (joule per second)? The world 5000 gigawatts, US 1000 gigawatts, city 1 gigawatt, a house 1 kilwatt
- If it's electricity generation, how much land space do you need / power density?
- How much is green premium ie additional cost to go green?
Making Things
- Reinforced concrete (concrete bricks with steel rods) in buildings, bridges
- Concrete = cement + water + sand and gravels; cement is made by burning limestone (calcium + CO2); 1 ton of cement releases 1 ton of CO2
- Steel = pure iron + carbon; pure iron is made by melting iron ore (raw) with coke (coal), releasing CO2 in process; 1 ton of steel releases 1.8 tons of CO2
- Other materials: plastics (cheap byproduct), fertilizers, glass, paper, aluminium
- 3 areas where CO2 emission occur in manufacturing and their solutions
- electricity needed to run factory – solutions refer to Plugging in
- burning of fossil fuel to heat up eg iron ore – electrification
- CO2 released in the chemical process – carbon capture
Plugging In
- Challenges
- Our demand for reliability vs intermittency of solar/wind/hydro power – high and low swings both bad, causing fluctuation of power cost / strain on power grids
- High relative cost of transmition (eg from sunny to cloudy area) and storage (battery)
- Generating energy (besides fossil fuel, solar, wind, hydro)
- Nuclear fission and soon fusion. Best carbon free alternative – only option that provides steady supply 24/7 at large scale. Needs much less land / concrete steel glass c/p solar, hydro, wind (note: making stuff emits CO2). Nuclear power accounts 20% US electricity, 70% for France
- Offshore wind. More steady supply, getting cheaper
- Geothermal. Pumping water underground to absorb heat from hot rocks, and come out another hole; not land efficient
- Storing energy (besides storing directly in lithium battery, which efficiency hard to improve)
- Turning electricity power into various other forms of power (pumped hydro, thermal, cheap hydrogen) then release it back to electricity when needed; all experimental, energy loss along the way
Growing Things
- Livestocks. Cow releases methane in burp/farts as it digests grass; poop releases nitrous oxide when it decomposes; both are many hundred times more harmful than CO2
- Fertilizers. Making (heating, transportation) and applying (unabsorbed nitrogen releasing to air) fertilizers releases GHG
- Planting trees is overrated; only absorbs 4 tons over 40 years per tree, but once burned down, all released back to air
Transportation
- Solution in sum: electrify all cars, and use alternative fuels (biofuels, recycled liquid carbon fuels) for the rest, as batteries too heavy for planes & cargo
- Beyond EV: hydrogen fuelcell cars. Hydrogen can be isolated from eg methane; mix with oxygen can product electricity & heat, release only drinkable water – process called electrolysis; electricity via hydrogen allows faster recharge than EV battery cars, but after electrolysis, compression, transportation etc. lose 70% of energy
- Hydrogen fuelcell also a solution for renewable energy storage – converting to hydrogen first