Plant 25 pct light spectrum used
Total 6 pct max efficiency photosynthesis
0.1-2 pct in practice
Sugarcane 8 pct?
1pct global energy to make fertilizer
By far the most efficient fuel by volume is coal
50m gallons per hour used to cool coal plants?!
Wyoming mines, one produce 100m tonnes per yer, 4t per second
Germany 50sq km coal mine, will become a lake
Largest tracked vehicle in the world?
Can an organism/protein be synthesis to process bitumen into single chain hydro carbons cheaply?
Energy roi for conventional oil is 25:1
Oil sand surface mining 5:1
Steam injection 3:1
Corn oil barely above 1:1
1g helium from fusion = 23t coal
Binding energy needed to repel electromagnetic force
Em force large distances, strong nuc force small distances
Mass lost in binding -> energy released in fission or fusion
Curve of binding energy peaking at iron
Larger atoms naturally decay
Weak nuc force governs decay?
Radioactive isotopes formed w solar system
Alpfa decay lose helium nucleus
Beta decay loses electron, actually neutron splits
Electron capture proton forms neutron
Only source of helium underground and very little, through decay?
Bombarding uranium w neutron, split into 2 nuceli, varies depending on collision energy
Releasing neutrons, hitting more uranium, etc
Get chain reaction
Radiate gamma rays -> energy -> heat water power turbines
Control the reaction otherwise runaway meltdown
Absorb extra neutrons -> steady stream of gamma
Boiling water, pressurized, and heavy water reactors
The latter allows higher temps and efficiency, no need to enrich uranium
Thermal neutron ambient temp
Only some isotopes are fissile - split when hit by thermal neutron
Some isotopes are fertile, can be converted into fissile - can capture neutrons through breeding
Bombardment of fertile isotope with fast neutron
Controllably convert into fissile
Nuclear rods contain various elements good at absorbing neutrons
Uranium in sea water 3mg oer cubic meter? Dissolved out of mountains and carried out to sea through rivers
8b tonnes in sea?
Too exp now, 3k usd per kg from sea water
Yellow cake - concentrated uranium after dissolving oxides with sulphur
Then convert uranium oxide depending on type of reactor
Uranium hexaflouride split in centrifuge into u235 and u238
Possible to split with laser but not yet scaled up for production use
Optimistically 20 watts per sq meter for solar panels
Everywhere in us gets 100-200 watts per sq meter of sunlight?
US consumption 1kw per person?
Equatorial often not best for solar
30deg north and south
Small microiverters allow the panel not to suffer if a part is occluded
Less toxic chemicals
Over 15pct efficiency
30pct efficiency drop when converting to ac
So dc for industrial uses more efficient
Hhigher temp, higher effiency
Need cooling and solar tracking
Too high wind requires turbine shut off
1mile spacing between large turbines due to efficiency impact with close spacing due to wind impact
10+ TW theoretical available wind energy in US
Cats kill a lot more birds than wind turbines
Collisions with antennas even more
Paraguay gets over 100% of its energy from hydro - actually exports surplus.
Each geographic region needs to tap 8nto the resources most readily available for that region. E.g, wind in central and coastal us; hydro pacific northwest and southeast; solar southwest
Pico- (1m drop) and micro-hydro plants
Hydro, standing, mosquitos, malaria
Desalination takes energy
Energy production requires water
Best have a lot of one, or we will have neither
Biofuel highly inefficient- less than 0.5pct per sq mt
Wind is more thn x2
Solar is more thn x10
12yr avg car ownership
Also time to get another 10b ppl
Feeding mouths vs feeding cars
Avg power consumption of boeing 747 is about 140MW
While flying consuming as much as 100k US homes
Intercontinental 747 12h equivalent 150 us homes for 1 year
If full, 1 passenger in that 12 hour for an average American total home electricity consumption for a year
Fuel efficiency drops with speed due to air friction?
Can save energy consumption just by lower speed limits
18000 Jules per meter for a jetski
Food uses 6x more energy to grow it than what it yields when consumed
Nasa used hydrogen fuel cells for Apollo missions. And that's where drinking water came from.
Energy value of food vs energy cost of production