Floating Solar Panels [Your Ultimate Guide]
So far, solar power has been great. From reducing environmental pollution to cutting the cost of energy production, solar power has solved most if not all problems of conventional power production methods.
However, the lack of enough space to set up solar panels has been a major drawback of solar power production for the longest time.
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But now there seems to be a potentially reliable solution for this obstacle:
Floating solar panels.
Floating solar panels present a new method of water surface use and land conservation for other crucial activities such as agriculture.
Think of how floating solar can reduce the negative impacts of direct sunlight and wind in water bodies. It’s an all-in-one solution that’ll touch various aspects of the ecosystem.
So, what’s in it for solar panels? The following guideline has all the crucial information you need to know about this land-sparing and low-carbon energy source.
What are Floating Solar Panels?
Floating solar panels are an emerging invention in which solar panels are installed floating on a water body with the support of rafts and floaters. These panels are also known as floating photovoltaics (FPVs) or floatovoltaics.
Floating PVs are very similar to conventional solar panels but come with a whole lot of benefits to reap. Floating solar plants are mainly found in lakes, man-made ponds, and reservoirs.
An analysis by IEA shows that floating solar is 20-50% cheaper than thought. Due to this, a 43% floating solar power growth is expected by 2040. Floating solar panels, if fully exploited, have the potential to even exceed these speculations.
Solar power is becoming increasingly popular, and floating solar power generation is on the same trend.
The impact of climate change on water bodies is at its peak. Ice in water bodies is melting-10,000+ lakes are at the risk of having ice-free winters if the temperatures increase by 4℃. In point of fact, these climate change impacts are worrying.
However, thanks to the sheltering nature of floating solar panels on water, there’s hope to significantly mitigate these climate change impacts.
What are the System Components of FPVs?
Component | Role/Description |
PV modules | The actual solar panels harness solar energy and transmit it to be converted into usable power. |
Floaters | These are a series of interconnecting plastic rafts where the solar panels sit. |
Mooring system – Anchors | These provide support to the solar panels floating on the water surface, right from the water’s floor. The commonly used types are vertical load, drag embedded, and suction anchors. |
Mooring system – Mooring line | This is the line connecting the solar panels’ floaters and the anchor below. The strength of the mooring line depends on the weight of solar panels that need to be supported. |
Combine box | This is where the output of all the solar panels on the array is gathered so that it can be fed to the central inverter. |
Central inverter | This is a huge component of the FPV, whose role is to convert DC to AC for transmission. |
Transformer | The transformer steps down the power for easier transmission. |
Cabling | These are the connections made to integrate the solar panels, combine box, central inverter, and transformer. |
Transmission system | This is the inland connection line used to transport the power to where it’s needed. |
Floating walkways | The access point of the solar panels from the inland side. Crucial when the solar panels need to be serviced. |
How Do Floating Solar Panels Work?
Moving forward to how floating solar power generation is done, it all starts with the collection of solar energy by the highly efficient solar panels.
The output of all the solar panels is merged in the combined box then sent to the central inverter.
The inverter, just like in a normal PV setup, converts DC to AC for transmission.
The power from the inverter is sent first to the transformer to be stepped down and then fed to the transmission system for conveyance to the end-user.
Deployment of FPVs in solar water bodies is a win-win situation. As the panels block excessive heat from seeping into the water bodies, they themselves get cooled, improving their energy productivity.
The cooling effect is capable of increasing the annual energy production of floating solar panels by 6%.
If you think about it, the floating solar panels’ efficiency and the entire working principle is a brilliant idea that solves a pretty good number of issues.
Floatovoltaics VS. Ground Based Solar Panels
Factor | Floatovoltaics | Ground-Based Solar Panels |
Performance | Enhanced performance due to the cooling effect | Performance is impacted by overheating |
Maintenance | Lower maintenance due to the cooling effect that protects the system’s components. | Overheating may lead to damage of components; hence more frequent maintenance is needed. Land upkeep needs are also relatively higher compared to the water upkeep needs of a solar plant. |
Space needed | A 1MW floating photovoltaic plant needs around 2 acres of land | A 1MW ground-based solar plant requires 5-10 acres of land, which is way higher. |
Installation complexity | Working in a water environment somehow complicates the process | Ground-based systems (with good accessibility) can be installed at a fraction of the time required to install floating solar PVs. |
How Do FPVs Work in Water, Without Getting Corroded?
Thanks to the advanced technology used in production, floating solar panels are protected with corrosion-resistant materials that make them water-friendly. They are so brilliantly designed that they can even survive frozen water.
Even with this, Floating PVs should only be installed in calm water bodies to prevent damage by water waves and excessive water interaction. It’s the reason why it has been impossible to install solar panels in the ocean.
What are the Costs of Floatovoltaics?
Setting up a 1Megawatt floating photovoltaic plant would cost around $1-1.2Million. This is a pretty huge amount for the upfront cost. The cost of floaters takes up almost half of the entire cost
The good thing is, there’re so many benefits (including cost-benefits) to enjoy throughout the lifespan of the floating solar plant.
Even better, there’re ways to make floating solar panels more cost-effective. Here’s one great idea:
Set up the FPVs in areas where other power generation plants such as hydrothermal plants exist.
This reduces the need to spend extra money to distribute the power generated by your floating solar power set up. The complementarity of floating solar and hydrothermal has been excellent in a test project in the Alto Rabagao reservoir.
Floating Photovoltaic Installation
The installation process starts at the anchors. These are installed on the seafloor. Holes are dug and the anchors installed deep enough into the soil for enhanced support. Anchoring the solar panels is one of the most crucial steps of the installation process.
Floaters are installed on the water surface, ready to receive the solar panels.
A mooring line is used to connect the anchor to the floaters
The solar panels are safely floated on the water surface, supported by the floaters.
The combine box, central inverter, and transformer are installed and connections are made from the solar panels to the combine box, inverter, then to the transformer, and finally to the transmission system.
Lastly, floating walkways are installed alongside the solar panel system. This is very crucial as it allows easy access to the solar panels when they need servicing.
Before going further, I must mention that the floating solar power plant design varies depending on:
- Water body function
- The type of PV module available
- Orientation of the panels
- Coverage needed
Who should install floating photovoltaics?
A team of well-qualified solar technicians and water/ marine engineers are suitable for this type of project. Usually, these specialists are part of a big private organization or government agency.
Advantages of FPVs
Increased energy production capacity
An 18-hectare floating solar panels farm plant behind Yamakura dam in Japan is capable of powering 5000 homes. Note that the 18-hectare is ‘water surface space’ taken by the FPVs.
Source of clean, renewable energy
Solar power from floating PV systems does not pollute the environment and can be used time and again. The same 18-hectare plant of floating solar panels in Japan is saving more than 8,000 tonnes of CO2 a year. Isn’t that incredible?
Reduction of land-use pressures
Solar is land-intensive, so floating solar is a brilliant solution for this. Even in countries such as the USA, where land for solar production is sufficient, there’s so much to reap from FPV.
Reduction in water body evaporation
Floatovoltaics have great potential to reduce the rapid evaporation in water bodies currently happening due to rising temperatures.
According to a University of California, Davis study, covering the California aqueduct with floating solar panels would prevent 9000+ acre-feet of water from evaporating daily.
Minimal maintenance
Due to the cooling effect, very little maintenance is needed for FPVs. This is, of course, dependent on the kind of installation done.
Limits harmful algae growth- Algae bloom is a major threat to water bodies. One of its causes, increased light infiltration, is reduced by FPVs and hence could go a long way in mitigating it.
Disadvantages of FPVs
Floatovoltaics are highly efficient, space-saving, and very beneficial to the blue ecosystem. However, they have their downsides.
Here are some floating solar panel disadvantages:
The initial cost is extremely high
As seen in the cost section, setting up a 1Megawatt FPVs plant would cost around $1Million. Obviously, this is way high compared to what their ground-based counterparts would cost.
However, note that the same floatovoltaics could prevent water loss worth the same amount per year.
Interfere with the natural look of water bodies
If a strategic approach is not leveraged, solar panels floating all over the water surface could interfere with the natural look of water bodies.
Sunlight does not reach the deeper parts of the water bodies
As much as we’re for the idea of shading, it can go overboard with the poor installation design of the solar panels. This could negatively impact aquatic life deep down the water body.
Cleaning the solar panels is not easy
Despite the low maintenance needs of floating photovoltaics, they still need frequent cleaning. This may not be as straightforward as cleaning ground-based solar panels.
Not suitable for everyone
Solar panels are expansive projects that would be insensible for a single household. This means that this power generation technique is limited to large-scale power production needs.
Even in water bodies, there’re some instances such as shadowing from surrounding mountain ranges that could make floating solar power generation impractical.
Related Questions
Can floating PVs be combined with hydropower facilities?
Yes, it’s one of the brilliant ideas to reduce the running costs of floating photovoltaics plants. A study by the DOE actually found out that 379,068 freshwater hydropower plants could seamlessly combine with floating solar panels.
What are the environmental impacts of floating solar power plants?
The impacts of floating solar power plants are both positive and negative.
Positive impacts include reduced evaporation, cooling of water bodies, and reduction of harmful algal blooms.
The negative impacts may be interference with the natural look of water bodies and reduction of sunlight in deep-sea environments. Note that the latter only happens when the solar panels are not properly spaced out on the water surface.
Are floating solar panels the same as residential solar panels?
Yes, for the better part, floating PVs are typically residential solar panels. Just a few modifications are done to make the panels water and freeze-tolerant.
Takeaways
Solar production is incredible but land-intensive. The solution to this obstacle is not covering all our rooftops with solar panels or clearing forests to avail free land, it’s installing floating solar panels.
It’s fair to say that floating solar technology is still in the development stage. But one thing is for sure, there’s so much for it in the future.
The floatovoltaics market size is growing (expected to hit $2.7 billion, according to US-based research), so you can tell things are only going to get better.
For those looking to invest in renewable energy, floating solar is a worthy consideration.