My 16-year-old nephew Alex was perplexed by the TV ad that General Motors ran during the Olympics.
"So, why is it better to grow my fuel, not drill for it," he asked. "Doesn't that mean less food for people?"
Well, yes, Alex, it does - and it's now clear that biofuels aren't great for the environment, either.
"And where will the hydrogen come from for those fuel-cell cars?"
Good question, Alex. There are only two ways of manufacturing hydrogen. One is to build plants that convert natural gas to hydrogen, but that would soon lead to a shortage of natural gas.
You already know the other way from your school science lab. Take a couple of wires, attach them to a battery and dip them into a beaker of water. Presto, you convert H{-2}O into hydrogen and oxygen. Trouble is, the battery goes dead very fast, because electrolysis of water takes a lot of electricity.
The bottom line is auto makers still haven't figured out how to build a practical or affordable fuel-cell vehicle and, in reality, there's only enough hydrogen to drive around a few very expensive prototype cars and city buses for photo ops. You'll probably be my age, Alex, before you see the so-called hydrogen highway.
"Speaking of electricity, GM's Chevrolet electric car looks pretty cool, but where would all the power for electric cars come from?"
That, Alex, is the big green question ... or maybe it's not nearly as green as some people would have us believe. The fact is, about half of North America's electricity is generated from coal-fired plants, and roughly 20 per cent is generated from fuel oil and natural gas. So unless an enormous construction blitz in nuclear power plants occurs, most new electricity demand will have to be supplied by fossil fuels.
"But what about electricity from water, wind and solar?" Alex asks.
Another good question. Hydro is an important source of power in Canada and there is more potential in northern Quebec, Labrador, Manitoba and British Columbia.
The United States, however, has very little potential, as rivers are already pretty much dammed up. Wind is a rapidly increasing source of electricity, but currently contributes just 1 per cent of North American supply, and there are a number of reasons why it will take a long time to get past 5 per cent.
Photovoltaics are an expensive niche supply, but of no significance in the big picture.
I guess the most important point is that electric power is already in rather tight supply, so renewable sources are going to be badly needed without trying to fuel the car fleet.
But generating electricity isn't the whole story, Alex. Once you generate it, you've got to get it to the consumer.
One of the challenges with wind farms is that expensive, long new power lines are often needed, both because people don't like them nearby and because the most reliable winds are often in places where few people live. The same is true for hydro power from Canada's remote northern rivers.
The biggest problem, however, is that North America's long-distance transmission systems are already old and stretched to the limit. Building new ones will require trillions of dollars, and then there's the NIMBY problem.
A typical example is the long struggle that British Columbia Hydro and Power Authority chief executive officer Jane Peverett has had in expanding overstretched transmission lines from B.C.'s Lower Mainland to Vancouver Island.
Tsawwassen residents continue to oppose the project even though it mainly follows an established transmission corridor. Part of the angst about high-voltage transmission lines is fuelled by alleged health effects - despite authoritative scientific studies which consistently debunk that myth.
The challenge with expanding electricity supply doesn't end after it is generated and moved to the cities and towns where it's needed.
Perhaps the most precarious part of the whole supply chain is aging municipal distribution systems.
A recent outage among the labyrinth of wires and transformers beneath Vancouver streets disrupted power to a large portion of downtown businesses and homes for several days. A B.C. Hydro spokesperson commented at the time that finding the root cause would be hard because the increasingly overstretched system is 50 years old and badly in need of renewal and expansion.
Those same comments would accurately describe the fragile and unreliable state of power distribution systems in the vast majority of Canadian and U.S. cities.
A final point: The power-source-to-wheel efficiency of electric cars is low. Power-source-to-wheel efficiency is calculated by multiplying efficiency ratios (energy in versus energy out) of all parts of the supply chain, from the power plant to the transmission system and local distribution systems to the battery and, finally, the electric motors that drive the wheels.
While the actual efficiency varies with power source, region and vehicle, conventional gas or diesel hybrids consistently deliver higher efficiencies than all electrics, with the added advantage of superior range and convenience.
So Alex, back to those GM commercials. Advertisements almost always feature a product you can buy, but here we see ads for cars the company doesn't sell, powered by energy sources that either aren't available or are already supply challenged.
"I think I've figured it out," Alex says. "GM believes that people seeing their commercials won't think about these things, so they'll just feel good about the company."
Right on, Alex, Some advertising experts call it "creating a halo effect." I just call it green washing.
Gwyn Morgan is the retired founding CEO of EnCana Corp.