Here’s a very solid and accessible article on population growth and sustainability from the World Future Society, though I’m not sure it provides any “new news.”

Yes, we’re consuming resources at an unsustainable rate, and that rate will only increase for the foreseeable future. Right now, we’d need an Earth about 1.6 times the size of our own to provide the resources that our population consumes annually. And as each year passes, the number becomes larger.

Put another way, there was a moment during a day this past September at which humankind had consumed all the resources that would be naturally renewed in the entire year of 2012. Soon, that moment will be in August; a decade or so later, July.

So what to do?

Each of the cleantech business plans featured here represents my main answers. They’re here precisely because I believe they contain some level of breakthrough technology that, if implemented, will move the needle associated with humankind’s potential to sustain itself.

Let’s take an example: the cutting-edge concept of aeroponics. If I were speaking to a group here, instead of writing, I’d ask for a show of hands. How many of you believe that our current approach to agriculture, with its ever-increasing quantity and potency of chemical fertilizers and poisons, can sustainably support a population of seven billion, on a direct climb to 10 billion? I wouldn’t embarrass the few who had raised their hands, but I would present a few facts that show how completely unsupportable this notion is. I would ask if anyone knows the average distance that the food in our grocery stores traveled by diesel truck to get there. I would congratulate those who know the answer (1200 miles). I would ask if that model sounds sustainable. I’m confident that, within a few minutes, I’d have a large percentage of the audience converted to the concepts of aeroponics, bioaeroponics, and aquaponics.

Of the other “big ideas” that I support in terms of sustainability, the most important are probably those that drive education. The most frightening challenges we face in dealing with our skyrocketing world population are rooted in ignorance. Uneducated people tend to have more children and fail to educate them, thus perpetuating the cycle of poverty and runaway population growth. That’s why I think the business plans that will develop rural off-grid/ microgrid electrification, e.g., microwind and mid-sized wind, are so important; they will foster education in regions of the world in which it’s currently extremely rare.

Others address climate change, like this unique approach to carbon-neutral synthetic fuels.

Again, each of these cleantech business opportunities is there for a reason. If you know anyone who could potentially play a role as a partner or investor, please let me know.