Our electricity grid can be powered by renewable energy much easier and faster than our transport sector. All we need to do is hook enough renewable energy into the grid and it’s distributed to it’s place of use.
The transportation sector presents an entirely different problem. It all has to do with “energy density”. Oil is an absolute powerhouse when it comes to energy density at around 46.4 MJ/kg while our best battery technology is Lithium-Ion at around 2.54 M/kg. So a tank of gas stores vast amounts of energy when compared to a battery pack. That’s the first problem. Here’s the second:
Electric transportation seems to be a reasonable solution but we can’t move over to electric because we simply don’t have the electrical generation capacity to recharge all those electric vehicles. Not by a long shot… A mind-bogglingly-huge longshot. Fact is if we all rushed out today and bought an electric vehicle we’d crash the grid!
Just in the United States our daily oil consumption is 20,680,000 barrels of which around 64% is used for domestic and commercial transportation, giving us a daily consumption of 13,235,200 barrels for transportation alone.
The energy contained in a barrel of oil is approximately 1.8 MWh so we multiply by 13,235,200 barrels to see that transportation requires 23,823,360 MWh daily. Now let’s look at coal fired power plants to see how many extra plants would need to be built to provide the energy for transportation.
In the US, there are currently 1,522 coal-fired generating units with a total production capacity of 335,831 MW (Megawatts).
To see what the average coal-fired power plant produces we only need to divide
335831 MW by 1522 which gives us an average of 220 MW output for each coal-fired plant. Now multiply by 24 to see how much power the average plant produces a day… 220 x 24= 5280 MWh (Megawatt hour).
We know from above that oil provides 23823360 MWh of energy daily for transportation so how many power plants is that worth? Divide 23823360 MWh by 5280 MWh (average coal plant) and we see: 23823360/5280 = 4512 extra coal fired units required – a tripling of existing capacity.
So these huge numbers tend to become a blur but to put some perspective on it; the US would need to build 100 coal plants a year for the next 45 years to cope with today’s transportation energy needs if we moved to battery electric propulsion!
Renewable energy is ultimately derived from the sun’s steady supply of gravity, heat & light to make plants, tides & weather systems etc.
These traditional fuels are what all life on earth, including humans, depended on until we began burning fossil fuels (basically sun’s excess energy that had been locked away)
fossil fuels are the alternative (if looked at without our current oil skewed view) because they are finite and only available for a very short part of our human history. And mostly used by a small percentage of the population living in high consumption western style cultures.