• Security incident: ISF was recently accessed by intruders. Please change your password, and change it anywhere else you used it. Read more

Sacrificing food for energy

Farm land gets 'spent' at some point in the exploitation process, unless its a rare slice of sustainably managed farm land. At some point, its not worth the costs of fertilizers, irrigation, fences, etc.

The shade created by the panels might permit some other uses...mushrooms, perhaps?
Rain water gathering and storage? Wildlife refuge? Worm husbandry? Bat roosts?

Most people, I suspect, would be rather shocked at the value of the corn that can be grown on a acre of decent land vs/ the cost of growing it.
When the depletion of the soil is taken into account, which it isn't, mostly, the equation gets worse. The apparent productivity of much of the huge farms in the U.S. is largely propaganda when all is factored in.

Of course, there is also propaganda concerning the value of the pv energy production.
It would be nice to get a clear view of all this; minus the subsidies and myopia about the future of the sustainability.

Food and energy are about to get expensive.
 
I'm a vegetarian, so i love soy based stuff.
and i love corn and all it's spinoffs (pollenta, tortillas, cornbread, pop corn, etc)
that said, we grow plenty (if not too much) and as someone pointed out, corn production makes for more CO2 in the atmospehere. If it were any other crop, i might be concerned, but not for these two.
 
...as someone pointed out, corn production makes for more CO2 in the atmospehere.
Not exactly. It is the scale of industrialized agriculture in general which does that, primarily through its heavy reliance on fertilizers produced using natural gas as a feedstock. If corn is the worst offender, it's because it has certain properties that make it a desireable choice of crop -- particularly as a crop for export. Soybeans require less fertilizer than does corn (being a legume, the soybean is capable of nitrogen fixation), but because corn utilizes C4 carbon fixation, it requires less water. A lot less. (Efforts are under way to introduce C4 carbon fixation into soybeans; that would really be something). Soybeans contain more protein than corn, but corn has more sugar, and that counts big if you're interested in making ethanol. Even if you're able to see the futility in that exercise, corn still generally comes out on top due to its greater versatility for use in processed foods.

It's entirely possible to grow either crop without the use of chemical fertilizers, and you can even eliminate the petroleum used in the combines and all that, making them completely carbon neutral. You just can't do it at the same scale.
 
Not exactly. It is the scale of industrialized agriculture in general which does that, primarily through its heavy reliance on fertilizers produced using natural gas as a feedstock. If corn is the worst offender, it's because it has certain properties that make it a desireable choice of crop -- particularly as a crop for export. Soybeans require less fertilizer than does corn (being a legume, the soybean is capable of nitrogen fixation), but because corn utilizes C4 carbon fixation, it requires less water. A lot less. (Efforts are under way to introduce C4 carbon fixation into soybeans; that would really be something). Soybeans contain more protein than corn, but corn has more sugar, and that counts big if you're interested in making ethanol. Even if you're able to see the futility in that exercise, corn still generally comes out on top due to its greater versatility for use in processed foods.

It's entirely possible to grow either crop without the use of chemical fertilizers, and you can even eliminate the petroleum used in the combines and all that, making them completely carbon neutral. You just can't do it at the same scale.

The c4 photosynthesizers, such as corn, are also able to be productive at higher temperatures. Beyond around 87F, most plants go into cooling themselves rather than growing, as I understand it.

Kudzu is likely a better crop than corn or soybeans, even though it is well hated and poorly understood.
 
The latest research by the FAO indicates 1/3 of all food is wasted worldwide.
That is 1,3 billion tons per year.
The average per capita loss in Europe and the USA is 95-115kg/year and in Sub-Saharan Africa and South/Southeast Asia it is 6-11kg/year.

Purple Non-Sulphur Bacteria (PNSB) can convert organic matter to hydrogen through photo-fermentation.
Facultative anaerobes such as yeast and lactic acid bacteria first convert the organic matter to organic acids and alcohols through dark-fermentation then the PNSB convert this to hydrogen using nitrogenase enzymes. Unlike methanogenesis there is little residue waste and the PNSB can be used as an excellent single cell protein(SCP) for animal feed or as fertilizer.
This process actually happens naturally in waste water ponds as can be witnessed by the purple/pink/red colour that is often visible on the surface. This is the colour photosynthetic pigments found in PNSB.

Researchers are investigating this process for the Mars Design Reference Mission(DRM) mission in order to recycle inedible biomass and waste into hydrogen and then recover the energy and specifically the water. Thus reducing launch mass.


Hydrogen has an energy value of 122KJ/g about 2,75 times higher than hydrocarbons.
Assuming that hydrogen makes up only 10% of all the food waste that is 130 million tons of hydrogen a year, equivalent to 2,5 billion barrels of oil per year.
 
The latest research by the FAO indicates 1/3 of all food is wasted worldwide.

:jaw-dropp

That may depend on how you measure waste. Is that direct waste, like food discarded because it's spoiled? Returned on plates in restaurants? Re-purposed for other uses? Some consider food fed to livestock to be largely wasted, compared to the yield of meat, milk, or egg.

I'm reminded of this award-winning heart-breaking short film about what happens with uneaten food in KFC restaurants in the Philippines.

 
:jaw-dropp

That may depend on how you measure waste. Is that direct waste, like food discarded because it's spoiled? Returned on plates in restaurants? Re-purposed for other uses? Some consider food fed to livestock to be largely wasted, compared to the yield of meat, milk, or egg.

I'm reminded of this award-winning heart-breaking short film about what happens with uneaten food in KFC restaurants in the Philippines.


From the report

2.1 Definition of food losses and food waste
Food losses refer to the decrease in edible food mass throughout the part of the supply chain that
specifically leads to edible food for human consumption. Food losses take place at production, postharvest
and processing stages in the food supply chain (Parfitt et al., 2010). Food losses occuring at the end
of the food chain (retail and final consumption) are rather called “food waste”, which relates to retailers’
and consumers’ behavior. (Parfitt et al., 2010).
“Food” waste or loss is measured only for products that are directed to human consumption, excluding
feed and parts of products which are not edible. Per definition, food losses or waste are the masses of
food lost or wasted in the part of food chains leading to “edible products going to human consumption”.
Therefore food that was originally meant to human consumption but which fortuity gets out the
human food chain is considered as food loss or waste even if it is then directed to a non-food use (feed,
bioenergy…). This approach distinguishes “planned” non-food uses to “unplanned” non-food uses,
which are hereby accounted under losses.

www.fao.org/fileadmin/user_upload/ags/publications/GFL_web.pdf
 
I'm reminded of this award-winning heart-breaking short film about what happens with uneaten food in KFC restaurants in the Philippines.


Thanks for that, most distressing.

The university in my local town producers 4 tons of food waste from the hostels per week.

At least this is now being recycled back into fertilizer for the university experimental farm.

One of the projects I am busy with is getting the food waste from the richer areas(shopping malls, hotels, restaurants, office canteens) recycled back into the soil to grow vegetables in the townships of South Africa.
 
Pics of the OT!

I wanted to catch some pics of the former food, now solar farm near me in the morning light:
67364ea3fb23a97d3.jpg


Hundreds of them are flooded! The ice this winter is really going to have it's way with them:
67364ea3fb238a50c.jpg


Their work in progress: installed panels on the right, frames waiting for installation on the left.
67364ea3fb23c1712.jpg
 
Largest Solar Energy Site of its Kind in the Western Hemisphere

I just learned that the site in the OT and my pics is world class. Costing $60 million to build, expected to generate 14.1 megawatts and 18 million kWh annually.

Here's their Press Release
 
Just a mile from me is a large field that used to yield corn, soybeans and the like, and is converted into a solar energy farm -- a sea of electricity-generating solar panels. Does this food-for-energy trade-off make sense?

as much sense as turning grain into fuel.

btw...there is lots of unproductive lamd that would be better suited.
 
I just learned that the site in the OT and my pics is world class. Costing $60 million to build, expected to generate 14.1 megawatts and 18 million kWh annually.

Here's their Press Release

Yikes. I wrote a book for McGraw Hill, long ago, which has been pirated.
I wrote to them 2 months ago and have heard nothing. Suddenly, I like pv less.
 
as much sense as turning grain into fuel.

btw...there is lots of unproductive lamd that would be better suited.

From the pictures, I think you probably got your wish. it doesn't look to me like corn would prosper any better than silicon will in that place. I would guess that the farmer was farming poor, undrained land marginally, and a better use for it may have been found. 50 acres? Three city blocks.
 
50 acres?

So what kind of crop yields was it getting?

What was it 100 years ago?

In my county that is a very very very small plot.

"NJRCEV will invest $60 million to develop and install the state-of-the-art, ground mount solar array on a 50-acre parcel on McGraw-Hill's property adjacent to the Corporation's two office buildings, including the Corporation's 180,000 square foot data center. "

So it could just be parking lots and blue grass or artificial landscape.
 
Last edited:
because what solar cells need is basically surface area, would it make any sense to have the solar array acting as the roof for a building or variety of buildings in the same location?
 
bikerdruid said:
panels are only efficient if they track, and remain perpindicular to the sun.
Depends on the technology--parabolic mirrors, focusing light on a solar boiler, cannot be perpendicular to the Sun and still work. ;)
 

ISF - Join now!

Every member here is approved by hand. No bots, no spam, just people who care about evidence and honest debate.

Membership is free!

Create your free account

Back
Top Bottom