Melissa Ferrin wrote:
Anne Miller wrote:
Melissa said, "How is this different than green beans?
Do some people eat pinto beans with the shell?
Yes, I guess, maybe picking them a bit earlier than you do. The beans for dry beans they don't pick until they are completely and totally dry on the vine. The whole vines are picked and then the beans are harvested via them being heavier than the dry vines/shells.
Michael Cox wrote:
Mark Reed wrote:It takes a given amount of energy to move a vehicle along its way. I can't figure out why it's better to produce it in a big powerplant to charge individual batteries than to have individual engines doing it.
Yes, that is exactly it. Large conventional power plants extract around 90% of the available energy as electric, compared to a car engine which would be lucky to extract 30% of the chemical energy as useful work. Both systems have other loses as well - producing and transporting petrol to pumps, EVs running power through cables. EV wins on efficiency by a considerable margin.
Plus, from what I understand there is a lot of extra issues that go along with manufacturing the batteries.
Some of these are real, most are massively overblown. Technology is evolving rapidly to make these issues go away, because those issues are also where a lot of the expense is. Manufacturers are highly motivated to make batteries cheaper, which in practice means finding alternatives to the expensive and problematic rare minerals.
Does an electric vehicle somehow need less energy to push itself along than a diesel vehicle does?
Yes - much more of the available energy goes directly to driving the motor, rather than being wasted in heat etc…
Does building a battery have a smaller impact than building an engine?
Sort of. If you lift the hood of a conventional car there is a huge complex engine full of moving parts. The equivalent engine of the EV is much smaller and simpler, with fewer moving parts. They basically don’t wear out so the lifetime cost of the engine is much less than for a conventional engine.
The battery tech itself is now largely recyclable.
Because, if not it seems to me that batteries might be even worse than engines
This analysis has been done to death by manufacturers, governments, independent environmental organisations etc… you can certainly point to individual aspects of the system that are not great (eg current use of small amounts of rare metals in batteries) but on balance the system is undoubtedly better than the conventional engines.
On top of all of the above, EVs allow the transport sector to be powered by the renewable entertainment sector. If we want carbon neutral or carbon negative economies we emphatically need this to happen. The alternative of a decade or so ago - biofuels - was an environmental and human disaster. Subsidies for biofuels drove deforestation, reduced crop area for available for food growing, drove up food prices globally (impacting the poorest people most heavily), and was actually still heavily carbon dependent as the crops used lots of fossil fuels in production (tractors, fertilisers, processing etc…).
The bottom line is that if we agree we need to have a carbon free transport system, then we need this, regardless of any harms. And the harms that get pointed to tend to be massively overblown.