solar power plant © anyaivanova - Fotolia

How Much Space Do Renewable Energies Need?

If we’re going to make renewables work, we need to start figuring out where to put them.

In 2008, the esteemed Al Gore told Obama he should demand that the US move to 100 per cent renewables within ten years.

We’re five years on now, but let’s pretend that Obama is just getting around to this memo on his list of things to do.

“Oh darn,” he says to himself. Then he calls you, because you are the most competent, forward-thinking, and good-looking person he knows. Your nationality is irrelevant.

In 2008, the esteemed Al Gore told Obama he should demand that the US move to 100 per cent renewables within ten years.

We’re five years on now, but let’s pretend that Obama is just getting around to this memo on his list of things to do.

“Oh darn,” he says to himself. Then he calls you, because you are the most competent, forward-thinking, and good-looking person he knows. Your nationality is irrelevant.

“[Reader],” he says with desperation in his voice, “How do I power a country with only renewable energy? Please make this happen immediately.”

Let’s get started then.

The key is to work backwards. Begin with the future you want to see and trace the steps back from there. Obama has only got a few years in which to do this, so there’s little possibility of a new technology saving the day, no deus ex machina to replace existing capacities. The core renewables – solar, wind, biofuels and hydro – are going to have to do the bulk of the heavy lifting (let’s exclude nuclear for the purposes of this thought experiment).

Having done all the background research and begun implementation, one of the first practical obstacles you’ll run into is the problem of space. How much room will all those wind farms take up? What kind of land will we need to sacrifice in order to obtain the necessary space?

At a conservative estimate, powering the United States through solar photovoltaics alone would take up 25,921 square kilometres, or a patch of land roughly the size of Massachusetts.*

This is a sufficiently large logistical problem that one would assume others around the world have done extensive analysis of the problem in their own countries.

Unfortunately, this isn’t really the case. The logistical nightmare of finding all that extra room is fraught with a multitude of intractable socio-political problems: Whose land is given up? Is farmland too valuable to be used? This being the case, energy planning documents, even from otherwise very forward-thinking countries, have largely skirted the issue.

 Denmark’s IDA Climate Plan 2050, for example, is a 191-page document mapping a route toward the country’s desired objective: “That Denmark shall be 100 per cent independent of fossil fuels and nuclear power, when oil and natural gas resources stop.” 

Yet, at no point does the plan broach the subject of space. Denmark’s per-capita energy use is only about half that of the United States, but with a total area of 43,000kmto work with, you’d think they’d be wondering about such logistical questions.

The power density of renewable energy technologies is still quite low compared to fossil fuels, meaning that it takes more room to produce the same amount of energy. To match global power consumption through biomass would require the use of no less than 10 per cent of the Earth’s land surface.

The question of space is by no means insignificant on a global scale, and will eventually need to be addressed in countries like Canada and the US. We can count on increased efficiencies, and other technologies have higher power densities than biomass, but the shock of these space-related revelations is familiar to anyone who has ever come home from a yard sale with a car full of new stuff, only to remember that their house is already cramped: Where are we going to put it all?

It’s going to require some tough choices. Obama isn’t asking anyone to start looking into these logistical problems yet and (sigh) neither is Stephen Harper, but our long-term planning needs to face them head-on all the same. The space question has to be confronted sooner or later.

* It should be noted that annexing Massachusetts for the purposes of creating a solar PV state would likely create some voter dissent.

Stu Campana is an international environmental consultant, currently working with Fern Ridge Landscaping and Eco-Consulting in Milton, Ontario.

Stu Campana is an international environmental consultant, with expertise in water, energy and waste management. He is the Water Team Leader with Ecology Ottawa, has a master’s in Environment and Resource Management and writes the A\J Renewable Energy blog. Follow him on Twitter: @StuCampana.