Floating Solar Farms: The Future of Renewables for Land-scarce Countries?

Singapore recently deployed one of the largest floating solar farms in the world, which is slated to offset over 4,000 tons of carbon dioxide per year.

This feat of engineering was not easy to build — with COVID-19 delaying project roll out and unpredictable open sea weather posing unprecedented design challenges. Now launched, however, it is set to become one of the examples to follow in the deployment of floating solar farms in the open sea.

Singapore and Climate Change

Always at the forefront of innovation, the tiny tropical country of Singapore is one of the most successful and developed economies in the world. Which also means that it is a pretty big emitter of carbon dioxide, ranking 27^th in the world and first in Asia in terms of emissions per capita.

That said, the country has a slew of programs underway in the fight against climate change. Today, 95% of its electric power already comes from natural gas — one of the cleanest fossil fuels for producing electricity — with the rest coming from a mix of coal, oil, municipal waste, and solar. 

As an active member of the initiatives led by the United Nations Framework Convention on Climate Change (UNFCCC), Singapore has set ambitious green targets in its 2030 pledge, launching the Green Plan 2030.

Some of the plan’s key targets include planting 1 million more trees, quadrupling solar energy deployment by 2025, ensuring that at least 20% of schools are carbon neutral by 2030, registering only cleaner-energy model cars from 2030 onwards, and reducing waste sent to the landfill by 30%.

Sun, Sea, and Solar Power

Producing four times more solar energy — 1.5 gigawatt peak (GWp) by 2025 and 2 GWp by 2030 — solar energy is a noble prospect, but Singapore is a tiny country with little land to deploy solar farms. The country has already installed solar panels on the majority of viable rooftops, but it wants to do more to maximize its prime location at the sunny equator.

So, Singapore is looking to the open waters surrounding the small nation as the prime real estate for solar power generation. Working with Sunseap (the leading clean energy solutions provider in Singapore), the country has set up its solar panel farm in the Straight of Johor which separates Singapore from Malaysia.

The 5MW-peak offshore floating photovoltaic (OFPV) system (if you want to get technical) features a whopping 13,312 solar panels, 40 inverters, and over 30,000 floats. It’s estimated to produce 6 GWh of energy per year, potentially offsetting 4,258 tons of carbon dioxide.

And while it is not the first floating solar farm in the world, it is one of the first ones set up in the open sea. This is both an innovative approach and one riddled with many challenges. These solar panels are exposed to the capricious changes in weather and currents, unlike those that float in calm, enclosed bodies of water like lakes. As such, the best practices and lessons learnt from this project will surely guide future projects of this kind.

How Does It Work?

Similar to its land-based counterparts, one of the principle components of a floating solar farm is its solar photovoltaic (PV) modules, which capture solar radiation. The ones used on water are tilted to optimize drainage and maximize energy generation. They also use double-glass instead of the typical single-glass to enhance durability in wet and humid environments.

The PV modules are supported by an extensive network of six different types of floats. These are made with certified food-grade quality high-density polyethylene to minimize their impact on water quality. They are UV-resistant and designed to support a lot more weight than the 30 kg PV modules.

Below the sea surface, the structure is maintained stable using dozens of anchors with mooring lines. Additionally, reinforced underwater cables — one of the project’s principle innovations — run from the floating farm to a barge.

Also installed directly on the floating platform are Huawei’s smart string inverters. These convert direct current (DC) electricity into alternating current (AC) electricity, which is then usable in the power grid. Smart string inverters integrate AI and cloud capabilities, making them a lot easier to deploy, use, and maintain. Huawei’s model also ensures very efficient heat dissipation, making them ideal to withstand intense sunlight.

From the floating platform, electricity travels through the underwater cables to the barge, where it is then converted from low to high tension. After this, the energy feeds directly into the power grid.

On the performance monitoring and O&M side, engineers constantly monitor system output in real-time; they do so remotely using a mobile app. Several safety features are also in place, like monitoring cameras that provide live video feed along with dashboards and alerts to track environmental factors. Ultimately, a range of cutting-edge technologies render a reliable, stable, and safe system.

What’s Next?

In the future, we can only expect more and more reliance on renewables. Even in the past decade, these have become significantly cheaper and more efficient, thanks to breakthroughs in technology. With ambitious goals in place — and with the view to achieve net zero emissions as soon as possible — Singapore is surely the one to watch for innovations in the renewable energy space.

Of course, there is still a long way to go. The solar power energy sector needs to respond to a fair few challenges. The industry is yet to adopt a robust solar panel recycling system, which will become an issue as the tech in the industry develops quickly. Space is also becoming an issue — even on water there is the trade-off with shipping routes and the limitations of the specific conditions necessary to set up floating solar farms.

That said, even in the midst of the COVID-19 pandemic, the renewables industry maintained steady numbers, showing the commitment on the part of governments, enterprises, and the public. Looking ahead, we will surely see even further optimization with cutting-edge tech like cloud, AI, and IoT, so exciting prospects await on the road to carbon neutrality.  

Read more about Huawei’s smart PV and solar solutions.

Disclaimer: Any views and/or opinions expressed in this post by individual authors or contributors are their personal views and/or opinions and do not necessarily reflect the views and/or opinions of Huawei Technologies.