Michigan State University researcher David Kramer a Hannah Distinguished Professor of Photosynthesis and Bioenergetics leads an effort to improve fuel and food producing plants saying, “This is critical since it’s the process that powers all of life in our ecosystem. The efficiency of photosynthesis, and our ability to improve it, is critical to whether the entire biofuels industry is viable.”
The facts today are plants aren’t so efficient as say solar cells when applying some forms of comparison. The Michigan State press release explains saying, “Plants are less efficient at capturing the energy in sunlight than solar cells mostly because they have too much evolutionary baggage. Plants have to power a living thing, whereas solar cells only have to send electricity down a wire. This is a big difference because if photosynthesis makes a mistake, it makes toxic byproducts that kill the organism. Photosynthesis has to be conservative to avoid killing the organisms it powers.”
The paper’s group is suggesting that replacing one of the two photosystems in plants that handle the light-dependent reactions with a photosystem from a species of cyanobacteria. The photosystems in most plants compete for the same piece of the solar spectrum, cutting the energy efficiency nearly in half. But some cyanobacteria absorb light from an entirely different part of the spectrum. Basically, it would be the biological equivalent of a tandem solar cell, which is very efficient.
Photosynthesis Compared Natural and Engineered.
That is opening the door to synthetic biology. The paper says:
“The techniques of synthetic biology may allow a more radical redesign of the photosynthetic apparatus for both bioenergy and food production applications. As mentioned above, the two photosystems required for oxygenic photosynthesis compete for the same wavelengths of light, reducing overall photochemical efficiency. An ambitious modification would be to maintain the two photosystems but engineer one of them to use the bacteriochlorophylls found in many anoxygenic photosynthetic organisms. . .
Substantial improvements can be envisaged even within the context of the two-photosystem architecture of current oxygenic photosynthesis . . .
Approaches in which photovoltaics are coupled to redox chemistry in photoelectrochemical cells and even living organisms also hold promise for solar fuels production. Numerous points of inefficiency in the natural system are amenable to improvement by using genetic engineering and aggressive techniques of synthetic biology.”
That is very likely correct. There may be great room for productive improvement of crops that produce food and fuel.
From a consumer’s point of view these kinds of study and research could well overcome the problems presented by the food vs. fuel arguments. Today a stopping of fuel production from crops would put some fuel crops back into foods, alleviating the need for such research. That wouldn’t be in the long-term interests of consumers.
The paper and the press release spend a major part of the point making effort to compare the sunlight absorption between plants and photovoltaic solar cells. It’s a different kind of argument than simply a vast increase in productivity.
“While photosynthesis is less efficient on a pure energy basis, it has the advantage of producing high-energy liquid fuels. (It also makes all of our food, and is thus essential for life). The paper summarizes several specific approaches to improving photosynthesis, some likely achievable in the short term, some more involved,” states the press release.
Continuing: “In truth, the competition really isn’t fair unless the term “efficiency” is first defined. At a bare minimum it isn’t fair to compare plants that package the sun’s energy in handy little stored-fuel vessels (carbon-based molecules) to solar cells that just take the first step of converting the sun’s energy to jazzed-up electrons. Fairer would be to compare plants to solar cell arrays that also store energy in chemical bonds.
The point of the comparison is not to make us throw plants on the compost pile, the researchers said. For one, efficiency is only one consideration among many in the choice among energy technologies. More important are life-cycle costs, the capital cost and valuation of the environmental impact of a product from its creation to its destruction.”
This research might be the starting point leading the exploration of why plants are so inefficient and what can be done to improve their efficiency. Genetic engineering and the more aggressive techniques of synthetic biology – the marriage of biology and engineering to design and construct systems and metabolic pathways not found in nature – could speed things up considerably.
But that would lead to an even more entrenched and far reaching special interest opposed to consumer’s interests – the genetically engineered organisms (“GMO”) mob that has rooted in across the planet much like the global warming crowd. The anti GMO crowd is often even more strident and unreasonable than the global warming folks and has already played a significant role in limiting food supplies to the poor and hungry – particularly in Africa.
All this makes the Kramer led group’s efforts be of extreme importance. A wider view as your humble writer is proposing needs considered beyond the simpler comparison with photovoltaic solar cells. Perhaps the strategy is slip in some more research without anti GMO attention, but that seems a very poor bet, indeed.
This research needs acclaimed as a “breakout” into further improving the production of food and fuel. The political world will go its own way as special interests apply pressure, but consumers have to know from the richest where food and fuel costs don’t matter to the poor where food and fuels are matter of life and death that science can work to make both more, better and much cheaper. It’s something politics will have to take into account.
By. Brian Westenhaus