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Looking Beyond Corn and Sugarcane For Cost-Effective Biofuels
carmendrahl writes "The abundance of shale gas in the U.S. is expected to lower the cost of petrochemicals for fuel and other applications, making it harder for plant-based, renewable feedstocks to compete in terms of price. In the search for cost-competitive crops, companies are testing plants other than traditional biofuel sources such as corn and sugarcane. In this video, you can see how a company is test-growing a relative of sugarcane, which is expected to yield 5 times the ethanol per acre compared to corn."
But corn ethanol is already the perfect way to enrich campaign donors in Iowa and the other farm states. Why should the guys getting rich off corn ethanol agree to share the government loot with other biofuel producers?
So when do solar panels become effective enough to replace growing a plant to harness the sun's energy?
I suspect that the break-even point varies depending on what you want to do. If you want electricity, photovoltaics get a substantial boost (plants may still turn out to be cheaper, for sufficiently large installations, if you can grow a zillion acres of generic combustables with minimal human intervention and then shovel them into a slightly converted coal plant or something; but the poor efficiency of the conversion from thermal energy to electrical energy will hobble you, and it will cripple you in small-scale installs). If you want a hydrocarbon-fuel substitute, the ability of organisms to synthesize all kinds of neat organic compounds is going to be quite a trick to replicate, even if you have unlimited electricity.
Also depends on location: given suitably robust solar cell packages(ideally with some fancy catalytic autocleaning coating), you could convert surface area on large structures into PV sites with just an occasional visit by the installers-with-climbing-gear. You wouldn't want to try crops under those conditions. A desert area, with plenty of sun but next to no water, would also be decent PV territory but bad planting ground. A large patch of arable land would have the opposite conditions(though it might also have competing food producers; but luckily, while it's illegal to use poor people for biofuel, it's legal to use food for biofuel and let poor people starve.)
The whole issue of sugar to ethanol suffers from several false economies including the usefulness in this case of water from the Colorado river which is not exactly surplus, and from the energy to distill and etc. Damage to the soil is a problem as is the whole issue of fertilizers etc. The USA is barking up the wrong tree with ethanol. It is a bad bad idea.
In the issue of a parent post regards competing with solar vs plants. Plants are at best thermally 1.5 to 2 percent efficient of sunlight. Solar cells are currently about 21%. The whole issue revolves around trading energy for which we currently have no effective use for energy that we can use. Biomass doesn't work well in cars so we only see it as a plus in the equation assuming we in our segmented economy fail to look at the total lifecycle costs.
Solar is already competitive and on price with standard generation means by fossil fuels.
Fossil Fuels have some key advantages.
1. Portability. You can take it, put it in container and ship it anywhere, or store it when you need it.
2. High Energy. You can get a good bang for 1 kilo of Fuel. Vs. batteries, or other forms of portable energy
3. Low tech maintenance. Fixing a problem in a fossil fuel engine is much easier then fixing a power turbine or a solar sell, we can use alternate parts if needed to.
4. Out of Sight or of Mind. Large Windmills covering the landscape, acres of solar panels, large dams... A lot of big infrastructure projects
It isn't that we couldn't go, however you need to know the tradeoffs and find ways of dealing with them.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
One advantage of solar power is that it is distributed, which helps with redundancy on the grid.
Plus, there are multiple ways of using solar power. Grid tie is one way. However, with the fact sometimes it is more expensive to pay a utility company to string a wire to a remote property than it is to set up an off-grid solar panel array, charge controllers, battery bank, and inverters, it isn't too far-fetched for people to just go with a bunch of panels and not bother with the electric grid whatsoever.
Solar is getting cheaper, mainly because China now has the critical mass of technology and willpower to stand behind it. It is only a matter of time before we start seeing each cell having a small MPPT controller so partial shading's impact is minimized, and perhaps even having the charge controllers or inverters built into each panel, so adding more usable watts might just consist of dropping another row of panels, plugging two power cables and a CANBUS cable, and letting the electronics do the rest. China wants this technology because it means that they don't have to deploy as many coal plants, thus less pollution.
Solar is coming to a point where it is less of a matter of "why", but a matter of "why not"?
To boot, solar panels have a long life. In 20-30 years, where most energy plants need to have a complete overhaul, solar panels might need to be washed every so often. An investment now may seem foolish, but given a steady return over the years, it may be wise over the long run. This is something that Germany understands, and is allowing them to wean completely off of both nuclear energy and Russian gas.