Where, exactly, did you hear this?
http://www.ars.usda.gov/is/AR/archive/jan12/crop0112.pdf
Hemp was 82.4 giga joules per acre, which I based my calculations on. Palm oil, which is king of the biofuels, is difficult to pin down in terms of yields (2 to 4 tons an acre) and joules per yield (play with numbers and it will be above or below that rate, but in any case, its not as versatile and replaces a much better carbon sink in its limited habitat--the more versatile crops needed for other climates are not this high). Outsize of algae, you need masses of acres of this stuff accounting for maybe more than the available farmable area of the earth.
The pet theories I'm talking about, are ones like reducing consumption of all types of energy, period, will a silver bullet that solves the climate change issue
Reducing energy consumption will reduce carbon emissions. This is an objective fact. You are confusing science with pet theories.
A theory is that burning oil now to create solar panels and windmills will lead humans to emit less carbon in the atmosphere over a 50 year span, which relies on changing the fabric of human civilization such that it no longer utilizes all surplus of energy for growth.
But we don't have to stop consuming ALL energy, just those forms of it which are causing major pollution in the atmosphere such as coal, gas, or petrol.
Biofuels cause problems as well and are not carbon neutral. My Orangutan buddy told me all about it and I would urge you to talk to him, but he is dead now.
planting trees, especially ones such as mangroves, would be a good start.
Now here is some major common ground