(just did some reading on means for capturing sunlight and how efficient they are; it challenged some of my preconceptions of where the solution might lie, so I though I’d share it with you guys too. I omit energy sources that are many thermodynamic steps removed from incident solar radiation, like hydroelectric, wind and waves – I *assume* these are extremely inefficient converters).
Chlorophyll (in plants, converts sunrays into ‘redox potential’ – useful chemical energy that can smash carbon dioxide and water together to form hydrocarbons – like sugar or biodiesel): ~100%
Conversion of chlorophyll-derived energy to useful molecules, like sugars: 50%
Factor in the energy spent by the plant so that it can live, and the sunlight reflected off the leaves, and your big green plant could theoretically convert just 11% (other sources quote 34%). Sugar cane is at the top end of the ones that have been measured: 4%; corn is 0.5% (corn is a major crop being used for bioethanol); wheat is 0.3%
Solar panels: 20%
I’d also like to know what the energy efficiency of a snickers bar or a sausage is (in terms of energy used by plants to make the individual components, energy to make the bar, energy to transport it to me, versus the energy it refuels my body with); my (largely baseless) guess is that it must be anywhere in the 0.000x – 0.0000000x% range. What a waste of sunrays!
UPDATE: http://venturebeat.com/2008/05/29/sapphire-energy-gets-open-checkbook-from-investors-for-algae-based-gasoline/ “Green crude” project putting bacteria in dirty water or seawater and extracting petroleum gets ‘blank cheque’ to make it happen, and quick. The Wellcome Trust is getting in on this, which is interesting – and probably a good sign for the viability of the technology
- WTF-of-the-day: Friday 30th May ’08
- A US cleantech company called Blacklight Power has raised $60m for a new, very clean form of electricity production. Nothing astounding there, really – cleantech is very much du jour. What’s “WTFotd”-worthy about this story is that the technology they claim to have developed runs against a key part of quantum physics: they claim that [...]...
- Microbial fuel cell not just a hydrogen creator, can also generate electricity
- I keenly follow latest breakthroughs in biomedical science, neuroscience and bionanotechnology – I figure I could share some of that on this blog, if it’s something you’d like to see more, please let me know. The Fuel Cell Bacteria: not only can Rhodopseudomonas palustris use light to create hydrogen, it’s also got an amazing superpower: [...]...
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