Let us take a quick look at how energy is moved around in the EV world...
Let us say you have an EV with an 85 kWh battery pack. Nice. Realize it took 500,000 lbs of ore that was mined, crushed, refined and then manufactured into all those little batteries. Eventually a factory process tested and assembled them into your pack. That consumed a lot of diesel fuel, coal and gas. That stuf isn't coming back - once and done with traditional geologically provided feedstock of fuel. That is the litmus test for a renewable energy source... is it once and done or can you economically make as much as society needs? That is given the notion that more nefarious ideas haven't been adopted. If so, all bets are off as to how this could speed along disintegration of critical elements of our modern world. If this descends into a global food fight, there will be no winners in my humble opinion. If there ever was a time to work together and put aside greed and lust for power - this is the moment.
As a side note, there are 290,000,000 cars on the road in the US. If they were all BEVs that would require the mining of 500,000 lb/car X 290,000,000 cars or 1.45E14 lbs of lithium ore just to have enough batteries to power those BEVs. Spoiler alert: Not going to happen because it is impossible for many reasons. Read on!
Now it's time to store some energy into that pack so you can drive your EV!
If you are thinking about installing a charging station at your home you have a couple of practical choices.
Level 1 - the least expensive and slowest method delivers 110V (in the US) on a 20 or 30 amp circuit.
What does that look like? Well charging time can be approximated by this equation:
Time[hrs] = (Battery Capacity in kWh) / (Charging station output in kW)
so with (110v X 20a ) / 1000 to convert from Watts to Kilo-Watts your level 1, 20A charger will take
85[kWh] / 2.2 [kW] or 38.6 hrs to fully charge that 85 kWh battery pack. That is a very long time, so Level 1 chargers aren't useful for automotive applications. They are pretty reasonable for golf carts. Or my favorite - the Twizy! Low cost, low energy, less damage to the roads, this thing makes a lot of sense as a commuter car. It's not family friendly, but that's a different topic.
So what does this look like for a more useful Level 2 charger operating at 240v and 50A?
240V * 50A / 1000 = 12 kW. That's a big improvement. Time now becomes 85 kWh/12 kW = 7 hrs from empty to fully charged. Easily handled in an overnight charge.
If we splurge on heavy duty cables, upgrade our electrical service and crank out 80A from that Level 2 charger we get a 4.2 hr recharge from zero to 85 kW. This is an approximation however as the pack will never be at zero and the topping off last few kW's take longer to store. But this is close enough. Don't forget most manufacturers have charging rate limits to keep that pack from getting too hot. Very bad things can happen if the pack over heats!
Faster recharging of a battery with different chemistry is possible but the ENERGY required is the SAME. Rate limitations aside. Energy is funny that way. When you focus on energy and not the particular fuel we see that there are no free rides. Faster charging or slow charging energy stored is the same. (ignoring thermal inefficiencies etc) How fast you can recharge is irrelevant to energy conservation. It does have a higher price tag as it requires thicker cables, bigger circuit breakers, multi-dimensional safety concerns... fast = $ that's it. The energy required is sized by what it takes to move the weight down the road including all of the losses, like aerodynamic drag, tire rolling resistance, performance requirements... thats what drives the energy storage size of the pack.
Now let's imagine EVERYBODY in the US had an EV and nobody used gasoline as a mobility fuel....
Lots of approximations exist for US daily gasoline consumption so let's pick 20 Million barrels of refined gasoline per day. Sound like a huge number? It is and that's just the US. This is a big global problem. Keep that in mind.
When we shift away from Gasoline to battery storage the originating energy supply has to come from somewhere. Solar and Wind are intermittent and do not ease the load on gas or coal fired power plants.
SO... 1700 kWh of energy exist in a barrel of gasoline. Amazingly energy dense!
20,000,000 X 1700 kWh = 34 billion kWhrs of energy needs to be created from something else... coal, gas and or nuclear to offset the gasoline that was being used. Again solar and wind are transient power inputs that due to there intermittent nature require the existing power plants to stay 100% on line. Let's not forget that CH4, and nuclear feedstocks are also very finite resources. Once and done remember?
Unless storage is found for the intermittent energy sources (which require energy to make and maintain) this is an intractable problem. This is where storing compressed air in huge volumes to eventually modulate over turban blades tied to generators at a constant speed starts to make sense. As long as there is low cost combustion fuel - makes no sense - remove cheap energy and - makes sense! Very clean, very inefficient, but very do-able. This is actually a very old idea used in underground mines in the 1800's. Many used underground water falls to capture air to run pneumatic tools. So many ways to adapt, but virtually all of them are less energy dense. That just means different!
What does a world without gasoline look like?
There are 1927 kWh of energy in a ton (2000 lbs) of coal. So 34,000,000,000 / 1927 = 17,644,006 Tons of coal need to be mined, delivered and burned at your power plant to replace the gasoline. EVERY DAY. That's a LOT of coal! If you consider typical US coal rail cars, thats 152,103 coal cars each day to replace the gasoline habit we have. So the scalability of this problem isn't even realistic with just coal as a replacement. But I digress. Just observe the enormity of the problem and switching to existing fuels isn't going to solve our growing energy needs.
Starting to understand the problem? You can use natural gas as a replacement if you like - similar result - a rapid acceleration of the depletion of existing feedstocks of energy. EVs are not an answer they just require a shift in originating energy supply and then require additional conversion inefficiencies which make it less optimal than just conserving our use of existing energy sources.
Replacing a vehicles energy storage media (gas tank with a battery) does NOTHING to solve depletion of energy feedstocks be they gas, coal or nuclear fuels. NOTHING. So when pondering what does solve this problem think about this...
What we need are alternate fuels like ammonia, blended hydrogen or other chemistries that can be true replacements for gas and oil. Manufactured by processes that use wind, solar or hydro to create. Shifting load from gasoline to our current energy sources merely accelerates depletion of existing resources. But it sure can make a lot of money for those in the supply chain of EVs. Considering where natural hydro power exists in large quantity - these geographies will be the next energy empires. These places will be where most of the renewable fuels come from in the future because they will win the cost/kW contest. Think Sweden... Maybe Greenland ( a lot of stored water at miles of height in that ice which makes for high potential energy which makes for beautiful hydro power!)
There is another solution. Much fewer cars and people who in turn will consume much less energy!
I do believe Hybrid powertrains have a place in energy conservation. So some battery applications actually help conserve our consumption and are part of a solution!
In summary: EVs can generate huge profits for those in the value chain, but just like other money making enterprises like manufacturing cigarettes and brewing alcohol, they offer no solution to energy depletion. In fact if implemented by mandate they will accelerate the exhaustion of these feedstocks. LOL, think critically!
The future will eventually arrive and with it we must adapt to changes in how we manage our energy.
Cars should be much lighter, the commuter vehicle should be like this... It is happy with a Level 1 charger and if all you need to do is get a few miles down the road and back - perfect! Wish I had one but for some reason we can't buy them in the US. This type of mobility could be supported on a residential wind power or solar panel installation too. So imagine the possibilities if we simply reduce the weight of our vehicles! I know, crash worthiness etc etc eventually, our feedstocks of cheap energy will help us adjust as we contemplate $/kg/kW. LOL, yep. Ultimately the "make rate" of the renewable fuel(s) and the weight of next generation vehicles will create a self limiting population of mobility machines. This is a new paradigm and will be difficult for most people to understand.
Trains and busses will be the primary means of long distance travel, just like they were in the early part of the auto age. BUT now we could mix modes of transport like the intermodal system - only for people! So many ways to reduce our energy use! If the bus were made to be a delightful experience the car would disappear, because who likes traffic jams, driving for hours and changing oil?
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