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Power Plant Converts Fruit and Veggie Waste Into Natural Gas For Cars
Zothecula writes "Some readers might remember the Mr. Fusion unit in Back to the Future that Doc Brown fills with household garbage, including a banana peel and some beer, to power the iconic time-traveling DeLorean. While we're still some way from such direct means of running our cars on table scraps, researchers at Fraunhofer have developed a pilot plant that ferments the waste from wholesale fruit and veg markets, cafeterias and canteens to make methane, which can be used to power vehicles."
Lots (around 40%) of harvested fruits and veg' rot in the field because the US consumer wont buy imperfect produce. Seems like a lot of potential fule out there.
"Have you ever thought about just turning off the TV, sitting down with your kids, and hitting them?"
The Parent post everstates the case, a lot of imperfect produce becomes tomato sauce, potato flakes, strawberry puree, applesauce, carrot juice, etc.
There is a lot of agricultural waste, some scratch and dent from retail, and a LOT of uneaten or wasted food from restaurants.
I expect there are some enzyme or bacteria treatments that can cause this mash to release more starches or sugars before the fermentation phase begins.
Does it rot in the field, providing fertilizer for the next generation of crops and thus reducing the overall costs due to the fact so much artificial fertilizer doesn't need to be used? It isn't waste if it is actually being used for something.
But when they rot in the field, the nutrients go back into the soil. If you plan on collecting all this fruits and vegetables, in order to capture the gases from them rotting, you also have to have a plan for returning the compost back to the fields. Not saying it's impossible, but can you get more natural gas from these things that it takes to transport them back and forth between the field wherever the gas is harvested?
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
My preference is to consume the fermented fruit matter prior to the generation of methane.
I am not interested in articles about life extension advancements.
Methane gas is recovered from many land fill sites. Nothing new to see here, please move along.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
It is better because it converts just about anything, including waste biomass we already generate. With corn and sugar based fuels, whole crops needs to be grown (and probably subsidized) to meet the modern demand for fuel. Ethanol and other biofuels have already been shown to be not quite as cost-effective as originally hoped, but with this system, we can start harvesting landfills for fuel.
Fermentation is a very passive process as far as the plant is concerned. Very little extra energy is introduced into the system. Once the energy is exttracted the leftovers can probably be used as a livestock feed like many distilleries do with their dried mash.
Plus were also looking at a source material feedstock if you will that comes from waste that already exists, not Corn and Sugar Cane that would otherwise be feeding people and keeping the prices of those goods at a reasonable level.
Unfortunately the chemicals that industrial agriculture uses interferes with the nutrient cycle that you're thinking of. Because everything other than the plant of interest is treated as something to be killed off with insecticides, fungicides, etc., the soil microbes are killed off, and the survivors are in an imbalanced ecological state which means that they're more likely to act in ways not helpful to the crop. It all leads back to dependency on oil-based fertilizers and pesticides while the soil is little more than a medium to hold the plant upright.
Otherwise, your solution would fit right in.
Does it rot in the field, providing fertilizer for the next generation of crops and thus reducing the overall costs due to the fact so much artificial fertilizer doesn't need to be used? It isn't waste if it is actually being used for something.
Yes. The stalks, top leafs, roots, unripe or spoiled produce becomes food for the next crop, usually some other crop in a rotation. There's a lot of science behind this, too, as some crops enrich the soil, f'risnstance with Nitrogen, for the next crop which is more dependent upon it (usually something leafy) as an example.
A feeling of having made the same mistake before: Deja Foobar
Rather than using the methane in cars would be to run it directly into an electrical generation plant. More efficient. Local landfills are collecting the methane, one is uses it to power generators and the other uses the methane to heat city schools.
A friend of mine has designed landfills for Natural Gas production and recovery -- peak production in 50 years, with a life span of about 100 years. Not huge amounts, but as you say, sufficient for a small community or a local industrial park is possible with the proper planning.
Much more of this can be done, if people would get their community leaders to plan how waste is processed and disposed of, rather than the out-of-sight-out-of-mind most people adopt.
A feeling of having made the same mistake before: Deja Foobar
Not fruit farts. Bacteria farts. This is /. Get your science straight before posting. :)
Silence is a state of mime.
... Doc Brown fills with household garbage, including a banana peel and some beer, to power the iconic time-traveling DeLorean. While we're still some way from such direct means of running our cars on table scraps...
The Mr. Fusion only powered the Flux Capacitor not the DeLorean. The DeLorean still ran on gasoline and is why Marty gets stuck back in 1885 when the arrow pierces the gas tank.
"Is life so dear, or peace so sweet, as to be purchased at the price of chains and slavery?" - Patrick Henry
Simplest thing to do: put the pulp back into the juice. Alternatively, let it compost. Takes about a year to fully compost, but as long as you make sure to ONLY put organic (or at least thoroughly washed) produce into compost, you get some excellent soil back.
Those who can, do. Those who can't, sue.
It's absolutely possible to compost it. You can even compost things like coffee grounds (with the paper filter if you use one) and tea bags. Pretty much any solid vegetable matter, really (including breads/cereals). The only thing I'd hesitate to compost is tomatoes, unless you *really* want a lot of tomato plants in your garden (also, you increase the risk of introducing some tomato plant viruses into your soil).
This is nothing new. People have been using biogas in India for ages. I first learned about it over 30 years ago. The Indians use mostly manure, but any organic material can be used, the more plant products you use, the more biogas you get.
There's a book from 1980 called "The Mother Earth News Handbook of Homemade Power" that goes into it (and other 'green' technologies that work well on small scales) that goes into greater detail. You can find it for 4-5 bucks on bookfinder.com
Understanding the scope of the problem is the first step on the path to true panic.
Your use of PERIOD makes your argument that much more persuasive. Why should we stop biofuel research? Because you said so. PERIOD.
Where I live (Stockholm, Sweden), there are many households that have done this for years and the amount is growing.
Households throw their food waste in special paper bags and put in separate bins. The contents of these are then collected and processed into methane at a factory.
The incentive for housing cooperatives and households to join the program is that collection of food waste is free while collection of ordinary garbage is not. There should be less amount of normal garbage and thus the cooperation's garbage costs would be reduced.
"We mustn't be caught by surprise by our own advancing technology" -- Aldous Huxley
the US consumer wont buy imperfect produce
Judging by my experience in the USA, this is categorically untrue. US consumers will happily tolerate vegetables that taste of (slightly) crunchy water. What they won't buy is vegetables that look imperfect. Imperfections in the taste and texture are fine.
I am TheRaven on Soylent News
Burning stuff produces most energy at least cost, huh? Me thinks someone needs to go back to school:
From: http://en.wikipedia.org/wiki/Internal_combustion_engine#Measures_of_engine_performance
"Most steel engines have a thermodynamic limit of 37%. Even when aided with turbochargers and stock efficiency aids, most engines retain an average efficiency of about 18%-20%.[11] Rocket engine efficiencies are better still, up to 70%, because they operate at very high temperatures and pressures and can have very high expansion ratios.[12]"
From: http://en.wikipedia.org/wiki/Fossil-fuel_power_station
"Typical thermal efficiency for electrical generators in the industry is around 33% for coal and oil-fired plants, and up to 50% for combined-cycle gas-fired plants. Plants designed to achieve peak efficiency while operating at capacity will be less efficient when operating off-design (i.e. temperatures too low.)[3]"
From: http://en.wikipedia.org/wiki/Gas_turbine
"GE H series power generation gas turbine: in combined cycle configuration, this 480-megawatt unit has a rated thermal efficiency of 60%."
"A large single cycle gas turbine typically produces 100 to 400 megawatts of power and have 35â"40% thermal efficiency.[15]"
"Typical microturbine efficiencies are 25 to 35%. When in a combined heat and power cogeneration system, efficiencies of greater than 80% are commonly achieved." [80% or better is great, but limited applications]
And all these methods of combustion produce carbon emissions, even the gas turbines. Granted, smaller amounts, but not zero.
From: http://en.wikipedia.org/wiki/Solar_cell#Efficiency
"Single p-n junction crystalline silicon devices are now approaching the theoretical limiting efficiency of 37.7%, noted as the Shockleyâ"Queisser limit in 1961. However multiple layer solar cells have a theoretical limit of 86%"
From: http://renewableenergyindex.com/renewable-energy-questions/how-efficient-is-tidal-power
"Tidal power is actually incredibly efficient (85% efficiency) when compared to things like coal power plants (30% efficiency) which is where the majority of electricity currently comes from."
From: http://www.ftexploring.com/energy/wind-enrgy.html
"Mr. Betz pointed this out and then proceeded to prove, with solid physics and math, that the best that could be achieved by a wind turbine is around 59%. In other words, a perfect best-possible wind turbine would be able to convert almost 59% of the power in the wind into mechanical rotating power."
Looks to me like efficiencies aren't that far off from burned stuff alternatives, and at least solar has some head room to get a lot better. Wind and tidal are mechanical-to-electrical processes so you would expect them to be lower efficiencies, but still within acceptable ranges given the zero emissions.
So, my point? We need to bring up the efficiencies of non-combustible means of power generation for work and stop burning stuff! Burning stuff does us no good and, is not overall more efficient than wind, solar and tidal when combined in similar usage patterns. To use the "but-it's-the-most-efficient-way-we-have" argument is ridiculous because that's true only due to the oil, coal and LNG industries stifling research budgets and buying up (and then dumping in a closet somewhere) technologies that might change their dominance. The tidal, solar and wind technologies would be farther along if research budgets hadn't been cut in the past 30 years. Advances are coming quickly now that renewed funding has been
Carbon from renewable sources moves in a cycle. The carbon dioxide that is released by burning plants is absorbed by growing plants. Carbon, being an element, can't be created or destroyed except in nuclear reactions (something plants aren't capable of doing), so there can be no net carbon release from renewable processes. The reason why fossil fuels contribute to carbon dioxide release is because fossil fuels represent stored carbon over millions of years, from an epoch when carbon dioxide was more prevalent in our atmosphere.