By Jack Ganssle

The New Greenies

Published 7/18/2005

We embedded systems engineers are the new greenies.

Students hold marches for environmental reforms; politicians pander and defer action awaiting the results of more studies, but embedded developers build products today that consume fewer resources and emit less pollution that similar devices of just a few years ago.

For instance, most heating and air-conditioning controllers now incorporate features and technology to cut energy use. Even a moderate-sized building consumes an awful lot of power. Promise a 10% reduction and customers will crowd your lobby waving fistfuls of dollar bills.

(One smart president/engineer I know built a homebrew A/C system for his company. At night the equipment pumps cool desert air into the building's concrete slab; during the day the circulation reverses, extracting the coolth and cutting his A/C costs in half.)

Smart factory controllers optimize the use of energy and raw materials. Big locomotive diesels controlled by high-IQ algorithms go further on the same amount of fuel. In the auto industry very brainy engine controllers extract the last bit of efficiency from each gallon of gas.

Take Toyota's Prius, a hybrid which uses extremely smart electronics to manage an electric motor, engine and generator to drastically cut fuel consumption and pollution. We bought one late last year, waiting 6 months to take delivery. What passes for high fuel prices in the USA (I paid $6/gallon in Bermuda a few weeks ago) has created far more demand than Toyota can fulfill.

After 15,000+ miles I can report that the vehicle is astonishing. When the outside temperature is above 50 we average 55 MPG over all sorts of driving. In winter the number plummets to a still acceptable 48. In the city it's not unusual to see the MPGs pegged at 99 for 15 minutes at a time as we slowly snake through the traffic.

(Other Prius owners report different figures; my wife and I are gentle drivers and prefer to look ahead, take action early, and avoid jackrabbit starts and stops.)

No hybrid could exist without a lot of embedded technology. The electronics seamlessly switches between electric-only, electric-assist, gas-engine-only, and regenerative braking. Come to a stop sign and the engine switches off. First time that happened I thought the car had failed. During normal driving the engine turns itself on and off many times per minute, with only a barely-discernable twitch.

I'm told the brake pedal is merely an input to the computer. Sure hope they got that software right. But when braking most of the car's momentum charges the traction battery. Toyota reports that if one avoids panic stops it's likely the brake pads will never wear.

One of the great benefits of capitalism is its never-ending pursuit of efficiency. Offer a product that's cheaper to operate than the competition's and you'll (generally) succeed. And then the entire playing field evolves to a new, more efficient level as everyone adopts the new technology. Not many decades ago we were content to waste resources. Energy was cheap; plastics, chemicals, and steel all inexpensive. No competitive pressure existed to conserve. Today's business climate is very different, and we embedded engineers are the sole key to building new generations of products that meet this need.

Think about it: a fleck of silicon, plus plenty of clever software, can save mountains of coal and shiploads of oil.

That's a pretty darn good legacy for any embedded engineer.