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Solar Panels Plus Farming? Agrivoltaics Explained

We have a world population expected to  grow by 1.2 billion people within 15 years, coupled with a growing demand for meat, eggs and dairy, which soak up over 70% of fresh water for   crops, plus electricity demand that’s growing  even faster than population growth … what are   we supposed to do about all of that? Well, we can  combine two of my favorite things: technology and food.

Both of which I’ve been accused of having  too much of. But, could combining solar panels   plus farming be a viable solution to all of those  problems? Let’s take a closer look at electrifying our crops … not literally electrifying crops …  never mind … let’s take a closer look at adding solar to our farm land as well as some of the  side benefits … and challenges … it creates.

I’m Matt Ferrell … welcome to Undecided. The problem with solar panels is that they need  a lot of space to generate serious amounts of electricity. Agrivoltaics or APV for short,  combines agriculture with electricity generation by farming under a canopy of solar panels … and  there’s some really interesting recent examples that make a compelling case for it, but before  getting into that it’s a good idea to understand the challenges around solar parks in general and some of the solutions that have been developed.

Solar parks in rural areas have been around  for almost two decades. The major problem with this type of solar installation is that  the ground beneath the panels can’t be used, mainly due to the small spaces between the rows of panels which aren’t large enough for modern farming  equipment to pass through.

It is possible to convert a typical solar park into dual land use when it’s designated as a living area for  grazing by small livestock like chicken, geese, and sheep, as well as for beekeeping.

These animals are beneficial to solar farms because they reduce the cost of maintaining vegetation growth and don’t introduce any risk to the panels themselves. The same can’t be said  of something a bit larger like pigs, goats,   horses, or cattle … it’s a known  fact that cattle hate solar panels.

When more space is allowed in between the solar panel rows, crops can be grown there.   However, the space beneath the panels still isn’t usable and needs to be maintained.   This is considered alternating land use  instead of dual land use because there   are areas of the land that are one or the  other, not both solar and crops at the same time. The land between the rows will  be shaded during some hours of the day,   meaning you’re altering the characteristics of  the land and the types of crops that can be grown.

So what if we started to go vertical with our solar panels? That’s where we start to get some interesting alternatives to standard  ground mounted solar park style installations. Using vertically mounted bifacial modules allows  for more arable land.

And if you don’t know what bifacial solar panels are, they can collect solar energy from both sides of the panel. This type of installation would work particularly  well in areas that suffer from wind erosion, since the structures reduce wind speeds which  can help protect the land and crops grown there.

The bifacial panels also can generate more  power per square meter than traditional single faced panels and don’t require any moving parts. Then there’s also the option  of mounting panels on stilts, which allows farming machinery to pass underneath.

In this design you have to maintain a certain clearance between rows to protect the stilts   from the machinery, so there is a modest  arable land surface loss … usually 3-10%.   Many variations on this theme are currently under  active research.

Instead of fixed panel mounting, panels can be mounted with actuators, allowing the panels to tilt in one or two directions, which allows for both solar energy and plant growth optimization.

This can be particularly important during  the initial stages of growth for some crops. But what about growing crops  … UNDER … the elevated panels? You’d think that solar panels casting shade on plants would be a bad thing, but the way photosynthesis works makes things interesting.

Plants grow their mass out of CO2 with the help of sunlight. They literally are growing from the  air … BUT … not all available sunlight can be converted into biomass. After a certain threshold,  which is called the light saturation point, plants can’t absorb any more energy, so they need to get  rid of that excess energy by evaporating water.

If we oversimplify this, we can divide  the plants into two groups: “I’ll have my light supersized” plants and “can I order my  light off the kids menu” plants. That group, the so-called shade plants, are particularly useful in combination with solar panels, since the panels obviously block  some of the available sunlight.

Now sun plants are sometimes referred  to as shade-intolerant plants, which makes them sound like jerks. This is a slight misnomer, since these plants just require more sunlight than shade plants  but can also suffer from too much sunlight.

When any plant reaches their threshold, they  can suffer from ‘sunburn’ and heat stress,   just like me, causing increased amounts  of water evaporation … just like me. According to a report from the German Fraunhofer Institute for Solar Energy, nearly all crops can be cultivated under solar panels, but there may be  some yield loss during the less sunny seasons for sun hungry plants.

In the RESOLA project conducted  between 2016 and 2018 in the German area of Lake   Constance or the Bodensee as the Germans call it,  they demonstrated that during a relatively ‘wet and cold’ year in 2016 APV-crop yields were 25% less than the non-solar reference field,   but in the ‘dry and hot’ years of 2017 and 2018  the APV-crops yields exceeded the reference field.

That’s a sign that APV could be a  game changer in hot and arid regions. The amount of experience with agrivoltaics is still fairly limited and the big successes have been mainly with shade tolerant crops like  lettuce, spinach, potatoes, and tomatoes.

Which leads us to some of the  super promising examples that make a compelling case for agrivoltaics. But before I get to that, I want to give a  quick shout out to today’s sponsor … me!   Seriously though, be sure to check out my follow  up podcast based on your feedback and comments on these videos, Still To Be Determined, which  you can find on all the major podcast services out there or at stilltbd.fm, as well as a video  version here on YouTube. I’ll put all the links   in the description. It’s a fun way to  continue the discussion on these topics. Let’s switch over to The  Netherlands. Tiny as it is,   it is the second largest  exporter of food in the world! The company “GroenLeven”, a subsidiary of the  BayWa group, which is headquartered in Munich Germany, has started several pilot projects  with local fruit farmers.

Their largest site is in the village of Babberich in the east of  the Netherlands, close to the German border, at a large 4 hectare raspberry farm, which is about 10 acres for those of us not on metric.

They’ve converted 3 hectares into a 2 MW  agrivoltaics farm. The remaining part was left in a traditional farming setup. Raspberries are  a fragile, shade tolerant fruit that’s typically grown in rows covered with plastic to help protect  them from the elements and ensure high yields.

In this project the raspberry plants are grown directly under the solar panels, which have been   placed in alternating rows facing east and west.  This maximizes solar yield, but also protects the plants from the prevailing winds.

They did test traditional solar panels in this project, but they took away too much of the available sunlight, so they switched to panels with a larger spacing between the solar cells to let more light through.

The amount and quality of the fruit produced under the panels was the same or better as the fruit  produced under the traditional plastic tunnels. One big benefit for the farmer was the amount  of work saved from managing the plastic tunnels, which are easily damaged  by hail and summer storms.

In those cases fruits may become  unsellable from the damage, but they still have to be harvested anyway.  During the last summer storms, the fruits under the panels didn’t sustain any damage, while the  harvest from the reference field was destroyed.

Another major difference between the agrivolatic test field and reference field: the temperature was several degrees cooler under the solar panels.  Not only is it more pleasant for the farm workers, but it also reduced the amount of irrigation water by 50% compared to the reference field.

Even cooler is how the crops affect the solar panels. The crops and their limited water   evaporation actually keep the panels cool. Solar panels actually don’t like to be hot, since it   reduces their energy efficiency; the cooler a  panel can be, the more energy it will provide.

So just based on that, agrivoltaics appears  to be a winning strategy. If we were to convert even a fraction of our current  agricultural land use into agrivoltaics, a large portion of our energy needs can be met  … easily.

And with the added benefits in reduced water consumption, agrivoltaics can also be a  game changer in hot and arid regions of the world. So what’s keeping us from rolling out this  dual-purpose, game-changing system at a massive scale? What’s the catch? Energy production  is a different ball game from agriculture, which can slow down farmers  from embracing the technology.

But the actual obstacles are sadly  … mundane … and some frustrating. It boils down to the the not-in-my-backyard  effect (NIMBY), bureaucracy, and the free market. So let’s start with the NIMBY crowd.

Not all renewable energy solutions are receiving a  warm reception. Prime example is obviously the  sight and sounds of a giant wind turbine in the   vicinity of your home. Community pushback  from the residents of Reno County in Kansas   killed a proposed NextEra Energy  Inc. wind farm. Also in agriculture, there are examples where current laws enabled  building giant biogas plants that weren’t always   welcomed by the local communities. No matter the  reason behind the community outrage and pushback, it’s this type of reaction that has  killed or delayed many projects,   as well as made many local governments  gun-shy on pushing them forward.

So in order to prevent communities turning against agrivoltaics it’s important to control its spread, especially pseudo-agrivoltaics (a  practice to build large solar farms under the guise of agriculture).

In protecting the people’s interest it helps to build  community support, which is essential. The Fraunhofer institute recommends that 1. Agrivoltaics should be deployed mainly  where synergistic effects can be achieved,   for instance by reducing the  water demand for crop production.

And… 2. To maintain proper local  support, agrivoltaic systems should preferably be operated by local farms,  energy cooperatives or regional investors. With these guidelines in  mind, community resistance   against agrivoltaics can be kept to a minimum.

Next, rules, regulations,  and bureaucracy can also hold it back, which varies from country  to country or even from city to city. “As part of its agricultural policy, the EU  grants direct payments for land used primarily for agriculture. So, an important question  is whether farmland loses its eligibility for financial support due to the use of  agrivoltaics [….] … Whether the land is   mostly used for agricultural  purposes is decisive here”.

In the EU, agrivoltaic systems are usually  considered to be physical structures in terms of the building regulation laws, so they need  a building permit. In Germany for instance, it’s usually prohibited in rural areas unless it  doesn’t conflict with a list of public interests.

Agrivoltaics, however, isn’t on  the list of public interests yet. Lastly and maybe most important is the free  market, which is pretty easy to wrap your head around because it all comes down to costs and  investment.

Just like putting solar on your home,  the big number to look at is cost per kWh. Because agrivoltaic solar doesn’t yield as much energy per square meter  compared to a traditional solar park, on top of the construction costs, the  cost per kWh can be 10-20% higher.

And there’s the big question of who owns the solar panels. In the Dutch example, the farmer   wasn’t the investor or owner of the installation.  A farmer’s willingness to participate all comes   down to avoiding negative impacts to the crop  yield and having lower operational costs from   the solar panels.

In this case the solar array owner was able to demonstrate those benefits. The Fraunhofer institute found that farmers  are only willing to engage in a project if the crop yield never falls below 80% of the reference  field, but … that’s only if the farmer owns the solar array. That’s because the farmer can make  up the crop shortfall from the energy produced.   But that also raises the question, if they own  the array, how are they going to optimize the solar panels … for solar energy production or for  crop yield? For the highest energy production per square meter, solar parks win out.

For the highest guaranteed crop production, dedicated farming wins out. It all comes down to costs and investments.  Without government intervention through subsidies or price guarantees, agrivoltaics may not  stand a chance against other solar initiatives.

Agrivoltaics is a very promising concept that has  the potential to kill two birds with one stone:   helping our food supply and transitioning  us to a cleaner energy source. The main benefit comes from the fact that solar panels are great at reducing GHG emissions, without sacrificing arable land.

Especially  if we can convert land that’s currently being used to grow biofuel crops, like palm oil and corn  farms, into land for actual human food production  and consumption … or even reforestation, that  would be a huge win! Looking at the big picture and deciding where we want to go can help us find  ways to overcome the difficulties along the way.

Dave Borlace over at the ‘Just Have A Think’  YouTube channel created an incredible introductory video on the agrivoltaics concept as well, so  be sure to check out that video too. But what do you think? Should we be trying to use agrivoltaics  everywhere? Are there any other dual use renewable energy examples that you know about? Jump into  the comments and let me know.

And a special thank you to Patreon producer Rob van der Wouw  for all his help on pulling this script together. Thank you, Rob. And thanks to all of my patrons  for helping to make these videos possible.

If you liked this video be sure to check out  one of the ones I have linked right here.   Be sure to subscribe and hit the notification  bell if you think I’ve earned it.   Thanks so much for watching and  I’ll see you in the next one.

Source : Youtube

What is Community Solar, and how does it work?

Welcome to the solar energy channel where you will get an honest inside, look at all things solar. In this video, we’re going to be talking about community solar versus owning your own solar system. – I’m Charles – And I’m Warren.

And please be sure to subscribe to this video to be notified when we release future videos, just like this. – So, Warren help us understand briefly what is community solar? – Sure, community solar are large solar arrays that are put in place to serve the community.

Primarily for people who don’t have the roof space or who don’t own their home for them, give them the ability to go solar. Yeah, so it’s a hybrid approach between something behind the meter where it could go on their roof or on their ground to say a utility scale, something in between that.

That that’s exactly right, Charles. If you think about solar for people who put solar on their homes, it’s behind the meter versus these large farms that you see out there. It’s, in-between those to serve those people who can’t otherwise go solar.

So, someone who is enrolled in a community solar project, do they actually own a part of the solar system? – They do not. So that’s one of the downsides to community solar is that you don’t get to own it.

And along with that, you don’t get to take advantage of the incentives that come along with solar. Yeah so definitely one of the pros of ownership is getting the incentives. What is one of the pros of going with the community solar subscribership? – Yeah, one of the pros is that you don’t have that initial outlay or the expense of going solar.

You get to participate and use renewable energy without the initial expense. In addition, if you happen to be a renter, or if you don’t have roof space or a ground space for solar, you can still use renewable solar energy by exploring community solar.

One of the other reasons for community solar is the idea that as the project grows in size, it gets cheaper per panel. – Correct. – So therefore I can be buying power from renewable sources that may be a little bit cheaper per se, than if I went and bought it myself.

Correct, so if you’re buying your electricity from the utility company and you rent, or you don’t have space for solar, it might be less expensive for you to look into community solar if that’s an option where you live.

Yeah, it should be said that there’s quite a few states that do not have the opportunity for people to buy into this community solar idea. – Community solar is new, solar in itself is new, but community solar is just starting to take off in most of the states around the Mid-Atlantic region.

So you may or may not have it in your state just yet. – Thanks for watching. If you enjoyed this information, be sure to like this video and subscribe to our channel for future releases.

Source : Youtube