Low Impact

We could be using our roads as a source of renewable energy

I came across this story in a few different places - basically, researchers in Massachusetts are proposing that we could use our black asphalt roads as a power source.  The concept is straightforward.  The sun strikes the black surface of the road, and heats it up, the heat is transferred to a power generator (such as a Stirling Engine), and electricity is generated.

It has the feel of one of those ideas that makes you go “why didn’t I think of that?!”.  Australians in particular will know just how hot a black road can get in the middle of summer.  It literally does get hot enough to fry an egg on - imagine if that heat could be harnessed to generate power!  Even better, it would generate the most power when the weather was hottest…and when the demand for power to run air-conditioners is highest.

Obviously, roads aren’t engineered to be perfect energy generators - I’m guessing that wasn’t a primary design goal!  But what they may lack in efficiency, they make up for in sheer area.  For most of us, a quick glance out the window is all that’s required to see just how many square metres of asphalt are spread across our cities.

Looked at in that perpsective, we have already gone to the trouble of building a vast network of thermal solar collection units, right across the developed world…but haven’t plugged them in! :)  This is a great example of taking advantage of a renewable power source that is right under our noses…or at least under our cars.

As far as I understand, this is still all theory - commercial implementation is likely to be many years away.  But with roads being replaced every 11 to 12 years as part of normal maintenance, there’s certainly the potential to retrofit something like this to a road near you.

I’m always wary of the concept (beloved by some) that individuals don’t need to take action on climate change - that some scientist in a white coat will develop a magic solution tomorrow to let us live our lives exactly as we do today, guilt-free.  The reality is that any technological solution that would make our present lifestyles sustainable is a long way off.  We need to start taking steps to prevent dangerous climate change today, or even 10 years ago!

Right now, we all need to be looking at what action we can take as individuals and, through our politicians, as a society to reduce our environmental impact using what is available to us today.  Switching to green power to let the electricity retailers know that it’s worth the investment, lowering our households’ power consumption so we don’t need as much power in the first place and reducing our consumption of day-to-day items are all concrete steps that we can take now.

Nonetheless, it’s great to know that talented people the world over are investigating new, sustainable sources of power that in the years ahead might play in role in avoiding climate change.  I’m looking forward to seeing what else is on the horizon.

Categories: current affairs, energy, environment, green

Tags: energy, green energy, renewable, science