half the primary energy extraction of a comparable amount of electricity at
the wall socket, the game shifts at the retail energy sale. Retail to wheels,
even low-tech electric vehicles (EVs) are twice as efficient as the most
modern comparable internal combustion vehicles (ICVs). Modern EVs can
easily be four times as efficient as the best ICVs. Total EV energy consumption is at worst equal to an ICV, and can be half.
Step 4: Distributed PV
The last, but absolutely essential, step is a shift to renewables, emphasizing distributed PV. EV and PV are tightly interwoven choices, driven by
efficiency. Efficiency dictates the area required to collect a given amount of
solar energy; its importance becomes glaring when analyzing biofuels.
Global population is nearing 7 billion. Total world land area is 36. 8
billion acres, of which fewer than 13 percent are arable. That’s less than 0.7
arable acre per person. Widespread adoption of biofuels represents a decision to starve 2 billion poor people to feed the cars of the richest billion.
Putting It All Together (Or not)
For the complete picture, envision a motor scooter and a PV panel. An
electric scooter consumes well under 100 watt-hours per mile. A 200-watt
PV panel and microinverter can put more than 600 watt-hours per day on
the grid. Conservatively, that’s 5 miles of clean travel per day, at a cost many
Americans would find trivial. OPEC has no say in the matter.
This is a thought exercise, not a prescription. If you want longer trips,
or four wheels, or highway speeds, the near future holds many options.
The only real variables are the amount of PV required and the fraction of
oil displaced. All four steps represent progress, and the most effective step
is free.
A chorus of dullards grunts that hybrids will never pay for themselves.
But what car ever did? We need to remind critics that most vehicle purchases are emotionally charged fashion statements, not frigid spreadsheet
calculations, and that the moral dimensions of energy overshadow the
financial. Mingling PV with EV showcases an ethos that the general public
can’t imagine without help from a few style leaders.
Forty-two states allow grid interconnection. Turnkey PV systems cost
less than $7 per watt. Dealerships now sell and service EVs. The gates to the
high road are finally open. Most ASES members already think globally. It’s
time to act personally.
Andy Warhol’s art doesn’t speak to me, but this quote does:
“They always say time changes things, but you actually have to change
them yourself.”
Automotive engineer Dave Erb has developed vehicles using gasoline, diesel, biod-iesel, alcohol, natural gas, electric, and (since 1986) hybrid electric powertrains. He
lives within walking distance of the University of North Carolina at Asheville, where
he teaches mechatronics engineering.
