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Energy Systems and Sustainable Land Use: The Good, the Bad, and the Unexpected

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An often overlooked element of sustainability engineering and science is sustainable land use or sustainable land management (SLM). The United Nations defines sustainable land use as “the use of land resources, including soils, water, animals and plants, for the production of goods to meet changing human needs, while simultaneously ensuring the long-term productive potential of these resources and the maintenance of their environmental functions.”

It is important to appreciate that virgin ecosystems or lands associated with indigenous peoples are essential for assimilating atmospheric carbon dioxide.

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Given the fact that some renewable energy systems have egregious land use requirements, it is prudent to suggest that inordinate land use will mitigate or even ameliorate the emissions control benefits of these technologies. In light of the headlong rush to deploy renewables, it is essential to understand land use characteristics for different systems. This knowledge becomes part of the deployment calculus and enables engineers and planners to design and implement systems that are mindful of land use sensitivities. Clearly, given the complexity of sustainability challenges and the wide variety of renewable energy options that are available, it is crucial that clean energy be economically and strategically deployed at large scale and with a distributed resource strategy, if feasible. Repurposing land for some renewable energy systems with a consequential reduction in biodiversity which is crucial for assimilating atmospheric carbon dioxide is counter-productive. The twin challenges of reversing biodiversity declines and mitigating anthropogenic climate change with renewable energy systems must be addressed in concert.

The productivity and sustainability of a land-use system is determined by the interaction between land resources, climate change, and human activities. In the face of climate change and variability, selecting the right land uses for given biophysical and socio-economic conditions, and implementing SLM, are essential for minimizing land degradation, rehabilitating degraded land, ensuring the sustainable use of land resources (i.e. soils, water and biodiversity) and maximizing resilience.

Power Densities per Area for Various Renewable Sources

A graph showing area power densities for various energy sources is shown below. The energy sources picked represent a mixture of both renewable and fossil fuel sources.

No alt text provided for this image

Figure references: 1 Powerlink article; 2 Strata 2017; 3,4 AD, 45% & 90% conversion, repsectively; 5 NEI Report 2015

It is clear that there is quite a range for power production per area for the various sources.

It needs to be emphasized that these ratings do not either disqualify, or for that matter, guarantee, the use of a particular energy source. This is stated because the key metric for this analysis is land use or sustainable land management.

For example, solar and wind are less desirable for large production systems because they will displace large tracts of land. On the contrary, both of these technologies are nimbler by the fact that they can be deployed relatively easier at small, even single household, levels.

The Good and the Bad

Three technologies, nuclear power, natural gas power plants, and anaerobic digesters to make RNG (renewable natural gas), all provide an option to coal, with less land management issues. It is noted that these options are not all renewable, particularly nuclear power which has its own challenges. Although natural gas (which consists primarily of methane) is a fossil fuel, it is more environmentally friendly than coal when used in power plants. However, natural gas must be transported long distances where leaks can occur. Natural gas losses during transportation can significantly contribute to global warming because methane is 25 times more potent as a greenhouse gas than carbon dioxide.

Large scale wind and solar technologies installations will be hampered by the large land requirements. However, deployment of these platforms in smaller energy generation scenarios is often ideal. Another constraint with wind and solar is that there is usually only one source of revenue generation which is the sale of electricity as AD generation of methane which can monetize multiple renewable product streams such as energy, fertilizer, and even water.

Methane production using anaerobic digesters (AD) is potentially very green and since the methane is generated on-site, the risk of GHG leaks to the atmosphere is significantly reduced. However, there are other obstacles for anaerobic digestion. Most concerns about anaerobic digestion concern issues such as odors, performance, and process control. Proper design and operation can address these aspects. There is also a sense in the environmental space that AD systems cannot be large-scale players in the renewable space and this concern is related to the fact that most AD's are unable to achieve much more than 45% conversion of solid biomass feedstock. However, a new generation of AD's with high conversion rates (90%) and multiple renewable products is in the deployment phase which will prove to be a game-changer for sustainable resource production as we know it.

The Unexpected

The land use analysis really did not reveal anything new with solar and wind platforms.

But it somewhat unexpectedly shows that BOTH natural gas and RNG systems are the predominant favorable technologies from a land use perspective.

Nuclear systems also score well from a purely technical and land use perspective. Unfortunately, even though public opinion has become somewhat more favorable, these plants also require lengthy times to design and install which is on the order of 10 years.

RNG AD high conversion systems have several advantages that are not readily obvious.

  • In many cases, high conversion RNG plants can installed at existing AD systems without minimal or no additional land required.
  • Existing operational AD systems can be upgraded to a high conversion mode using a "plug and play infrastructure" approach that requires far less capital with upgrades implemented in months, not years.
  • AD systems can be modified to almost double gas generation as well as generated high-valued products such as green ammonia and water.
  • Manufacturing multiple renewable products and associated off-take agreements facilitate project financing by using the agreements as collateral.

In summary, in the complicated milieu that is the sustainability and climate change space, one axiom seems to hold sway in that there will always be room for multiple technological platforms. The notion that there is a broad solution that is embodied as a Holy Grail or a universal panacea that may suddenly appear is wishful thinking. Practicing sound science and engineering and utilizing structured mass and energy balances appropriately in concert with judicious economic assumptions will take one far in devising insightful and elegant solutions for even the most challenging problems.

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Michael Keller's picture
Michael Keller on May 10, 2021

There are practical limitations on small scale renewable deployment, particularly solar. These include being placed where sunlight can reliably reach the solar panels as well as the being placed on structures that can support the panels. In passing, the presence of trees is unhelpful.

The cost to install the solar panels and limited production output means the majority of existing residential homes are generally not particularly suited for solar panels. Then there is the matter of payback on the initial investment.

From a land use perspective, facilities with very high energy densities (nuclear and natural gas) are much less destructive to the environment than green energy.

The proponents of green energy tend to overlook how stunningly land intensive the energy production resources actually are. Being unreliable is also unhelpful.

Peter Farley's picture
Peter Farley on May 12, 2021

Completly unsupported statement. In Australia for example studies have shown some years ago that 180 GW of rooftop solar could be installed on unshaded roofs. Allowing for solar canopies on carparks etc and the rising efficiency of solar panels that is about 250GW today. At the moment there is about 13 GW supplying 7% of demand so clearly if storage was cheap enough, behind the meter solar could supply more than 100% of electrical demand. This does not include solar thermal, small wind, geothermal, waste to energy, hydro, etc etc

Michael Keller's picture
Michael Keller on May 14, 2021

Energy (as in megawatt-hours), not power (megawatt) is what is what counts. A 100 megawatt power plant that works only works intermittently 25% of the time is not that useful.

Peter Farley's picture
Peter Farley on May 16, 2021

I am sorry I did not make it clear.

1. 13 GW of capacity supplies 7% of all electrical energy on the main grids in Australia (NEM and SWIS). In fact I underestimated it it is almost 10%. Therefore 250 GW would supply 10 x 250/13 =  192% of current electric demand.

2. A detailed satelite study by NREL in 2016 showed that 30% of US electricity demand could be supplied by 14% of roofs using 16% efficient solar panels. This study eliminated badly sited and shaded roofs. As 20-21% efficient panels are available now and 25% within 5 years, so the economic share of behind the meter solar will rise.

3. The Melbourne CBD has a large number of 35-60 storey buildings which cast long shadows and use a large amount of energy per square m of land area. A recent study by Monash University used half hourly insolation and shading data and showed that somewhere over 70% of electricity use could be provided by building mounted solar.

Pontification from people who don't even bother to study the facts is even more useless than theoretical studies

Michael Keller's picture
Michael Keller on May 14, 2021

Most roofs are not located or designed for solar energy. Theoretical studies divorced from practical reality are more or less useless.

Peter Farley's picture
Peter Farley on May 18, 2021

More than enough roofs are, see NREL study

Bob Meinetz's picture
Bob Meinetz on May 10, 2021

"Unfortunately, even though public opinion has become somewhat more favorable, these [nuclear] plants also require lengthy times to design and install which is on the order of 10 years."

Alan, your link (Statista) shows the average construction time of nuclear plants around the globe has dropped to less than 5 years. In the U.S. and other developed countries, however, where oil companies hope to replace existing nuclear generation with gas, regulatory roadblocks and legal challenges have been successfully employed to tie up nuclear projects in litigation, effectively doubling construction time and expense.

Alan Rozich's picture
Alan Rozich on May 10, 2021

Clearly, if other factors such as SLM come to the light, that opens the door more for nuclear and other options. I am not against nuclear. I think what is most startling is that many parties want to go large scale wind and solar without thinking through all of the implications.

Zark Bedalov's picture
Zark Bedalov on May 10, 2021

I'm all for the solar panels. On the roofs only, that is. I may install some on my roof soon. Seeing miles and miles of solar panels laid on ground in the most inefficient way I see the trees and bushes being removed. That is not how we hold on global warming. The trees are taking in CO2 and give us so much. By removing trees we contribute to global warming.

 

Peter Farley's picture
Peter Farley on May 12, 2021

1. Now that solar windows and vertical solar panels on sun facing walls are becoming economical, open countries such as the US can easily get 50% of their electrical demand from behind the meter solar.

2. There is no need to cut down forests for ground mounted solar farms. If Europe was to generate 1/3rd of its electricity from ground mounted solar it would require 550,000 ha = 0.13% of the land area the same as occupied by golf courses (about 540,000 ha), much of this land can be waste lands such as old gravel pits, landfill sites, road and railway embankments, old industrial sites etc

Matt Chester's picture
Matt Chester on May 12, 2021

Thanks for sharing, Peter. Your point about using otherwise useless lands-- brownfields, covered landfills, etc.-- is really just logical and should have very little resistance.

Now that solar windows and vertical solar panels on sun facing walls are becoming economical

What is the state of this tech? I've heard teases of solar windows for a while but haven't really seen commercialization at any real scale yet. Is it still the cost to implement? Or is the generation from them too much lower than a traditionally positioned solar which is what makes the numbers still a stretch to add up? 

Peter Farley's picture
Peter Farley on May 16, 2021

I replied to this post earlier I don't know what happened to the reply. There is at least one manufacturer of practical  solar windows and a number who are applying solar to walls. At the moment they are both less cost effective than rooftop solar so until most of the rooftop opportunities are tapped out there is little need to pursue them. 

Matt Chester's picture
Matt Chester on May 17, 2021

Thanks for the reply! What about for new buildings, though? If I'm building a new office tower, for example, why wouldn't the economics dictate I put solar both on the roof and the windows, since for the single building owner that's all I have access to? I don't care much about the other rooftops of my neighbors that haven't been solarized, I just want to max out what I can control

Peter Farley's picture
Peter Farley on May 18, 2021

There are some buildings applying vertical solar to walls and a very few using it in windows. As you know the building industry is very conservative, I think it will take 5-7 years before they become common, but the vast majority will still be on roofs. Up to 2-3 stories on an efficient building rooftop solar will provide more than enough energy

Peter Farley's picture
Peter Farley on May 12, 2021

I am not sure where your figures come from but they are backwards.

Some examples:

1. The recently closed Hazelwood power plant in Victoria Australia including its mine and cooling pond occupied and permanently destroyed more than 22,000,000 square m. Annual output was about 1,100 GWh  Wind turbines placed on farming land or in commercial forests use about 200-300 square metres each and produce 12-21 GWh each in that location. Using the worst figures means that 95 modern wind turbines would use 28,500 square m.i.e about 0.13% of the land taken up by the power station and mine. Now if we move to 6 MW class turbines near existing roads and tracks then land use will fall to less than 10,000 square metres.

2. In 2016 NREL showed that 14% of US roofspace could provide 30% of US electricity demand using 16% efficient solar panels. Now that 21% panels are available and hard stands, carparks, railyards, spectator areas at sportsfields etc could be fitted with solar canopies that converts to about 50% of electricty production requiring no additional land use at all

3. The Hambach mine in Germany and associated power stations will destroy about 90 square km over its life and produces about 55 TWh/y . An agri-Voltaic solar farm of that size would have as much or more agricultural production as open farm due to the benefits of summer shading and winter windbreaks but could add 15 TWh per year, without destroying any farms. Combined with behind the meter solar in surrounding areas solar can produce as much energy as Hambach with zero pollution and saving 9,000 ha of industrial land

4.  The fenced area of Palo Verde Nuclear plant with associated cooling water processing is about 18 square km it has peak capacity of 3,950 MW. This does not include the mine or the necessary share of the Hanford nuclear fuel processing area, which will at least double the area devoted to nuclear production.  4 GW/24 GWh of container sized batteries stacked two high needs 0.3 square km, 2,000 medium sized wind turbines to provide the energy require another half a square km,

5. The Darling Downs combined cycle gas plant requires 220 gas wells drilled over its lifetime plus waste water treatment plants, gas cleaning and treatment plants and well over 500km of pipelines. Ninety modern wind turbines which each have a similar pad size to the gas well and a battery field smaller than the power station would provide just as much energy.

6. Dryland farming around the world yields about $600 of food and fibre per hecatare per year. A 1 ha solar farm coupled with a 2 ha greenhouse can produce more food and $80,000 worth of power, would the farmers not be much better off. Experiments in India have shown a 30% increase in farm output in agrivoltaic fileds due to the benefits of shading/wind breaks

 

Michael Keller's picture
Michael Keller on May 12, 2021

Palo Verde produces about 33 million megawatt-hours of energy in a typical year. To match that, solar energy would require about 140,000 acres versus roughly a few hundred acres for Palo Verde.

You need to become more familiar with the ramifications of using diffuse, intermittent energy resources like solar energy that are badly affected by the planet’s rotation, location of the solar facility on the planet as well as the planet’s angle and position relative to the sun.

Excessive use of solar energy is a serious threat to ecosystems owing to massive land requirements. This is painfully obvious.

Michael Keller's picture
Michael Keller on May 12, 2021

Further, your assessment of infrastructure needs for nuclear energy becomes comical when contrasting similar needs for producing solar panels.

Then we have the bizarre situation of buying solar cells from China, a nation that uses coal in vast amounts for the energy needed to produce products sold to the West. Basically, renewable energy advocates provide massive monetary rewards to China that is, hands down, the the planet’s biggest emitter of CO2.

Peter Farley's picture
Peter Farley on May 13, 2021

1. Painfully obvious to no-one who studies the facts. Studies in India Australia and the US and even Switzerland have shown that various designs of solar farms actually increase agricultural productivity within the solar farm, by providing shade and windbreaks.

2. If the US was foolish enough to use agricultural land for high density solar farms to produce 1/4 of its current electricity demand they would take up slightly more than 3m acres

about 0.5% of the area used for cow grazing

 or 1% of cropland

or the same area used by railroads,

or 8% of the land used by ethanol and biofuels

or about 12% of land reserved for defense

or about half the area used to produce corn syrup

or about 50% more than the area of golf courses

3. Re Palo Verde 4,400 acres plus its share of the uranium mine - Ranger for example 19,500 acres + its share of Hanford 375,000 acres

4. Just because your government and ours handed the solar industry to China on a plate is not their problem it is ours, because of our backward looking governments. However you might be surprised to learn that over the last few years 40% of all solar and wind installations in the world have been in China and last year they produced 720 TWh vs the US production from wind and solar of 415 TWh. In addition the high quality low cost panels they are exporting are supporting decarbonisation throughout the world. They do have far too many coal plants but at least they are cleaning them up. By the end of next year the dirtiest Chinese coal plant will be cleaner than the cleanest US or Australian plant

Michael Keller's picture
Michael Keller on May 14, 2021

I’ve been in the power business for over 50 years, have earned several advanced engineering and business degrees, hold several patents and have written a book on energy systems. I am more than familiar with facts.

Most of the acreage around Palo Verde is untouched desert.

The US government does not control from where solar panels are procured, the solar facility developers buy the panels. 
 

You might be surprised that large numbers of green energy facilities installed in China are not actually used. You might also be surprised that hundred or so million dollars worth of wind turbines built offshore from the Fukushima nuclear disaster were dismantled - simply not cost effective. A gasified coal plant was built to replace the nuclear plant - that coal plant is remarkably clean and efficient.

Your claim about the dirtiest Chinese coal plant being cleaner than the cleanest US plant is unequivocally false.

Peter Farley's picture
Peter Farley on May 28, 2021

 “Research Note on U.S. and Chinese Coal-Fired Power Data” by Melanie Hart, Luke Bassett, and Blaine Johnson

Michael Keller's picture
Michael Keller on May 28, 2021

Your claim is utter nonsense; your cited references clearly have no idea what they are talking about and are technically incompetent. Large numbers of the older Chinese plants have, at best, minimal air pollution control features.  Ever wonder why the air is brown in so many Chinese cities? Their government is trying to clean up the air with better pollution equipment on the plants, but it is a struggle to balance the needs of energy for industry and their citizens  versus clean air. Kind of like the US in the 1960's.

In passing, the Chinese government has embarked on an ambitious nuclear program with large numbers of plants  on-line, under construction, or in design. Their ability to build their nuclear plants vastly exceeds that of the US (and Europe for that matter). Unlike the US, the Chinese are taking a balanced approached to energy production and will no doubt relegate the US to a has-been status. 

Bob Meinetz's picture
Bob Meinetz on May 15, 2021

"...various designs of solar farms actually increase agricultural productivity within the solar farm, by providing shade and windbreaks."

Peter, this is flat-out wrong. Anyone who's grown a garden knows crops will not grow without sunlight. You can use sunlight to generate electricity, or you can use it to grow crops, but you can't use the same energy to do both.

Peter Farley's picture
Peter Farley on May 20, 2021

You must be the most willfully ignorant person I have ever come across. Many areas of the world including the US have too much sun, Others have too much wind. some areas too much of both. Look up agrivoltaics. There are studies in Australia, India, Oregon, Texas, Japan, Germany and Switzerland that not only show that agriculture, horticulture and sheep grazing ncan not only co-exist but increase output within a solar farm.

But even if you were right as I said 8% of the land devoted to biofuels or 0.5% of the land grazed by cows would provide 25% of the US electricity supply.

 PS CdTe panels supply less than 2% of US solar output

Bob Meinetz's picture
Bob Meinetz on May 28, 2021

Peter, thank you, you make my job easy. Personal insults are the last refuge of a doomed argument.

No, there are no "studies" that show solar panels can co-exist with farming, and no, I won't "look up agrivoltaics". It's your job to support your argument with references - I don't have time to do your job for you.

I'm sure there are solar evangelists somewhere, who have created a little garden somewhere, that grows flowers or spices in between the panels. That's not farming - farming requires lots of sunlight. If you think wheat, or corn, or anything useful for human sustenance will grow underneath solar panels, you have no idea what you're talking about.

In 2021, farming also requires big machinery. This harvester, for example, wouldn't "co-exist" with your flimsy solar panels - it would crush them to bits.


 

Michael Keller's picture
Michael Keller on Jun 2, 2021

You do realize that using one's food supply for biofuels is utterly non-sensical from an economic standpoint? Worse, has no value in reducing CO2 as generally end up with net emissions. 

Growing crops requires sunlight - suggest you study biology more closely.. Stop with your outlandish claims.

Solar energy has value, but only used in the right place.   

Bob Meinetz's picture
Bob Meinetz on May 13, 2021

"2,000 medium sized wind turbines to provide the energy require another half a square km..."

Really? 2,000 medium-sized wind turbines on half a square km of land would be 52 feet apart from each other.

I think your calculator's broken.

Michael Keller's picture
Michael Keller on May 13, 2021

Bob is on target. For our Palo Verde example and assuming good wind availability (e.g. parts of plains of Kansas) need about 1 million acres. This acreage is essentially off limits to human settlement because of the potential for missiles (ice, blade parts) launched from the massive machines. The machines are visible for miles and are eyesores on the plains. Notice the machines are not located off of beaches on the East and West coasts.

Peter Farley's picture
Peter Farley on May 13, 2021

Of the 1 million acres the wind turbines alienate approximately 125 acres, the rest continues as farm land, rocky ridges, commercial forests etc.

It is not off limits to human habitation, what a ridiculous statement. In fact many rural counties in the US which have welcomed windfarms have increased population because the wind farm maintenance people live locally but mainly because the farmers and counties have more income through lease payments and taxes which allow them to employ more people

Notice that with the approval of Vineyard wind there will be a cascade of offshore wind in the US particularly on the Atlantic and Gulf coasts and floating wind on the West coast.

Matt Chester's picture
Matt Chester on May 14, 2021

Of the 1 million acres the wind turbines alienate approximately 125 acres, the rest continues as farm land, rocky ridges, commercial forests etc.

This is an interesting point, Peter. When people talk about the land-use of utility-scale solar farms, it tends to take the whole land, save for some types of specific vegetation that can perhaps thrive under the shade of the panels. But are you saying that wind farms are readily able to be combined with a more varied and perhaps valuable agricultural land? Are there specific types of crops that pair particularly well with wind turbines? I'd love to see some examples of dual use lands because, as you noted, that would be a huge win for the farmers, not to mention double positive land use for the climate. 

Michael Keller's picture
Michael Keller on May 14, 2021

All the vegetation has to be removed to avoid shading the solar panels and measures provided to keep dust from coating the panels. The dust is created by vehicles that wash and maintain the panels.

Solar panels are incompatible with farming. You guys are decoupled from reality.

The wind turbines in Kansas are typically located infields containing a wide variety of crops as well as pastures. The service area around the turbines and access roads are not farmed. Nobody generally lives within several hundred yards of the turbines, largely because western Kansas is sparsely populated. Very few turbines are located in the more populated (kind of a relative term) Eastern Kansas because the wind is insufficient to economically justify use of the machines.

With the realization that wind turbines can be dangerous (blades breaking apart, ice being thrown) the Europeans are mandating  set back limits. Then there are the matters of noise and visual pollution. That is one of the reasons new turbines are being located offshore. 

 

Matt Chester's picture
Matt Chester on May 14, 2021

Solar panels are incompatible with farming. You guys are decoupled from reality.

It's unconventional thinking, but sometimes that's what we need-- there are some serious projects being explored. They definitely come with sets of challenges, and the outcome is not yet certain-- but agrivoltaics can be a niche solution:

https://thecounter.org/agrivoltaics-farmland-solar-panels-clean-energy-crops/

Bob Meinetz's picture
Bob Meinetz on May 15, 2021

"Solar panels are incompatible with farming. You guys are decoupled from reality."

It's ok, after the first solar panels begin cracking and leaching cadmium telluride into the soil it will be too toxic for farming anyway.

"Cadmium is recognized as a toxic substance by the United States Environmental Protection Agency (EPA), which set a maximum contaminant level (MCL) for cadmium (Cd) of 0.005 mgL-1 in drinking water. Tellurium (Te), while not regulated by the EPA, has also been shown to have the potential to cause kidney, heart, skin, lung, and gastrointestinal system damage in rats and in humans."

M-m-m...how 'bout a nice fresh ear of Kansas "Solar" Corn?
Cadmium Corn

Matt Chester's picture
Matt Chester on May 17, 2021

Bob-- is that image you shared not just corn mold? https://extension.wvu.edu/lawn-gardening-pests/plant-disease/fruit-vegetable-diseases/corn-mold

Can you share a source where solar panels have created toxic farming land or crops, or are you just extrapolating to what might happen?

Peter Farley's picture
Peter Farley on May 16, 2021

Matt

Most windfarms are in open grazing land but some are in broadacre grain farms and some in forests and some in wastelands. There are no broadacre crops or livestock activities that I know of that are incompatible with windfarms, although some fruit crops which need frost to set the fruit may be better off away from wind turbines. Just Google wind turbine in grain farm

Some wind and solarfarms use existing roads with short driveways for access, others are on specially built access tracks. On balance my farming friends with wind turbines are very happy with them because on average including tracks they use less than 1/15 th of an acre of land, for which they are paid A$8-12,000/y each. The average gross revenue for that type of land is about $150- $500/acre. so a large farm which hosts 5 wind turbines gives up $50-$180 in revenue in return for $40-60,000 in rent. Even strawberry fields cannot make that drought and market independent revenue per acre. By the way the farmers often use the access tracks for farm activities and they are much better made and maintained than the average farm track.

A 100% renewable grid in the US will need about 100,000 onshore wind turbines to supply 35% of current electricity demand. If all wind turbines were concentrated in the 650m acres the US uses for grazing there would be one for every 6,500 acres of grazing land, reducing available grazing land by 0.0009%. If onshore wind was to provide 35% of all energy in an energy efficient economy the size of the US, the wind turbines would use 0.002% of US grazing land or 0.0008% of US land area 

 Solar farms are less efficient use of land, but recent developments in polinator friendly layouts, agrivoltaics etc, grazing instead of mowing has meant that solar farms can be moved away from dusty locations. Even in arid regions, the wind breaks provided by solar farms can reduce the amount of dust raised and the shade improves growth of shrubs, ground cover and horticulture. Even more recent developments have shown that sun sensitive fruit can be grown under partial solar cover in regions that are now becoming too hot for tradional orchards. Mr. Kellers comments on the way solar farms were built is correct but that is old practice and most solar farm permitting now requires solar farms to preserve and if possible enhance vegetation in some way.

A final illustration. In the Goulburn Valley in Victoria, there is not enough irrigation water for all the farms. Farmed unirrigated land produces $350-600/ha/y. A widely spaced tracking solar farm can produce the same or more agricultural value and $65-70,000 worth of electrical energy. 300 hectares of solar farms with 3 hectares of batteries can provide more consistent year round energy than a 200 MW gas turbine or about 10 times the revenue of a similar sized irrigated dairy farm in the same region.

Michael Keller's picture
Michael Keller on May 18, 2021

The gas turbine only needs a few acres of land and is not impacted by the weather.

Wind turbines in Western Kansas are located several hundred miles from the major load centers. The machines are located on the ridges of hills. The machines do not particularly impact grain and cattle production but the machines are a bit of an eyesore. While there are a few national parks (prairie not trees) in Western Kansas, the region is sparsely populated agricultural and grazing lands. Not sure of the lifetime of the machines blades owing to the severe weather in Western Kansas - very large hail is relatively common. Dust adhering or eroding to the blades also causes loss of efficiency. Bottom line, probably need several more years of operational data to get a good handle on financial performance of the machines on the US Great Plains. The machines do provide additional farm income, - the farms in Western Kansas are immense, approaching the size of entire counties on the US East. Absent government subsidies, the wind machines are poor investments.

 

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