An example is in a brave venture in India where a 10 kW prototype floating solar generation facility is being developed for placement in a pond. Pilot projects of this nature have also started to take shape in countries like Japan, France and Australia.

Rethinking Solar Farms for the 21st Century: Tapping Ocean Space

Lee Hsiu Eik, Research Engineer | Offshore Engineering Centre, PETRONAS Institute of Technology, Malaysia

Solar Panels, a once obscure and highly expensive race of renewable energy technology have, in the past decade progressively established themselves as a major component in the myriad of renewable technologies.  Much of the progress to date on harnessing the sun’s energy utilizing solar technologies are centrically pivoted on a handful of developed countries, with examples of more prominent players being that of Germany, Spain, United States, France and Japan.

One nonetheless, has to empathize with developing countries where priorities are naturally directed towards tangible and swift prowess into becoming a developed nation rather than developing ground breaking renewables or trading carbon credits; with a recent obvious exception of India which boldly, is in the process of expediting its renewable energy share on an impressive scale.

With rising environmental awareness and ever increasing oil prices, it is only a matter of time before alternative energy sources catches up with the rest of the world, developed or not. Restating the obvious, oil price was and will always be on a long term uptrend and such hydrocarbon sources of energy are of a finite domain; meaning, they’d eventually run out, even if it doesn’t happen in our lifetime. Although we have come a long way in improving efficiencies of our hydrocarbon fuelled machines with substantially reduced emissions, an increase in energy consumption driven by population growth and increased living standards can be thought to somewhat offset the latter by intuitively deducing, that which is conserved by quality efficient engineering would be more or less consumed by an inevitable increase in demand.

Stuck in this paradigm, one of the foreseeable ways to circumvent it is by revamping our energy mix, which has been discussed with much rigor in more recent times. In fact, several front end moves have been made within the past decade with case examples being a gradual shift towards gas based field developments as a cleaner fuel source in the oil and gas industry and the proliferation of wind farms on both onshore and offshore locations globally. Solar technologies are obviously not unmissed and are touted as one of the fastest growing renewable tech today with a yearly growth rate of 40 percent since year 2000.

To the layman, solar energy conversion technologies can be generically subdivided into two distinct categories – that of direct conversion via Photovoltaic (PV) panels or indirect conversion by principles of concentrated thermal energy. Both of these methods have their respective pros and cons and share the fact that their developments would typically take up a credible amount of land space. This would not be a problem if a country has too much free land space to begin with, coupled with low population density and perhaps scattered with long uninhabitable flat sunny terrains. Such is an ideal scenario where the government could, fairly easily, single out a sprawl of deserted land to build an intruding, glaring and land guzzling solar farm without losing out on votes and facing the wrath of nearby affected communities, without chomping down on rain forests, or without jeopardising arable land for agricultural purposes. Unfortunately, this is rarely the case as evident in many small developing countries especially when it comes to crowded regions of coastal cities or island states. Land in such instances is usually priced at a pocket crunching premium or specially reserved for infrastructure and agricultural initiatives, which will, in all logic take precedence over a solar farm project.

Delimiting our discussion here to a global reach it is prudent to note too, that approximately 50 percent of the world’s population are already living within 100 km of the coast. Living in the vicinity of water has been somewhat akin to the advancement of past civilizations and still obviously plays an important role in our current state of being. And with 70 percent of the earth covered in water, it only makes sense to make up for the lack of allocable land in many countries for mega solar farm deployments by bringing solar technology onto the water domain.  To some, this may seem like a ridiculously unnecessary notion but for small oceanic countries like that of mountainous Malaysia, crowded Singapore and populated Hong Kong, a water based innovation may be the key to the realisation of large scale solar energy generation facilities.  

A vast majority, if not all, of the small existing developments on floating solar farms globally have been centred on occupying idle water spaces in the likes of lakes, reservoirs, dams and irrigation ponds. These solar modules are typically of the PV type, resting on buoyant sub structures which may be made up of practically any sound structural concept with enough buoyancy to keep the PV array afloat to its desired water clearance.

An example of such developments would be to scrutinize Hydrelio, developed in a Research and Development partnership between France’s IFP Energies Nouvelles and Ciel et Terre which is based on a modular concept made of HDPE plastic foams capable of withstanding up to 190 kph winds. Along the same context, Japan and India are taking the technology head-on by spearheading developments on floating arrays of solar panels which would find application in unused surface water space of lakes, dams and reservoirs.

Not limited to mere closed bodies of water, there are also several concepts abound in the market for applications of floating solar cells suited for the offshore marine environment. Although there has yet been a proper documentation on any sort of sizeable offshore prototype deployment, it is irrevocably the future way forward as the technology will eventually take to the seas from closed water bodies.

Realising this, Det Norske Veritas (DNV), an independent foundation with presence in more than 100 countries has developed SUNDY; a concept of flexible hexagonal floating arrays of thin film solar panels that are compliant to incoming sea waves, a shift from their more rigid counterparts which would typically sit on pontoons or hull like sub structures for support and buoyancy. One of the technological benefits of ocean deployment is the potential to tap both the sun and waves in a hybrid approach to ocean power generation. Throw in wind and possibly, current into the fray and we will have a fully integrated energy island – which sounds rather farfetched from where we are today but some innovations are already pushing at these seemingly immovable walls.

Phil Pauley, for one, has developed what is called Marine Solar Cells which couples both solar and wave energy generation and is touted capable of capturing more energy per square meter than a standalone system; in short, giving you more bang for your buck and space.

What all floating solar energy generation facilities have in common is the inherent benefits of the hypothetically cooling effects of water on the solar panels. Noting that excessive heat has been shown to decrease the panel’s efficiency, particularly for silicon based panels, the natural water cooling effect will in theory translate into more efficient energy generation. In fact, research points out that this can lead to as much as a 16 % increase in power generation abilities, should the rear surface of the panels be kept cooler. So, besides navigating about the perennial problem of indispensable land space, barring anything else, a floating solar farm might just be a tad more efficient electric generation system as compared to their land based relatives.

This does sound like the Holy Grail to a solar powered future for small regions surrounded by water, but it is interesting to note that most commercial solar installations to date are based on land, save a few cautious but notable projects worldwide.

An example is in a brave venture in India where a 10 kW prototype floating solar generation facility is being developed for placement in a pond. Pilot projects of this nature have also started to take shape in countries like Japan, France and Australia. The United States is no alien to floating solar cells with developments like that of in Napa Valley where an array of solar panels now floats on a pond at the Far Niente Winery. Emulating such movements, Singapore has also made noticeable steps into the realm of floating photovoltaic systems with a test bed 5 kWp system installed in the Pond Gardens of Bishan Park which would function as a data acquisition platform for further research activities. Naturally being short of land, Singapore’s attention in floating solar panels as an alternative to roof top solar panels can be pre-amped without much difficulty. And with increasing number of high rise buildings in congested cities, it no longer makes much sense to install photovoltaic panels on roofs of a cross section that would barely meet the energy requirements of several floors of a multi-storey high rise. Factor in the shading effect from other buildings and it is evident that building integrated photovoltaic may not be the best solution for crowded city centres.

Of course, there are several exceptions to this especially when a new building is being built in a relatively uncrowded space and designed from the very start with integrated photovoltaic technologies and energy savings in mind; a good case study would be to read up on the Diamond Building in Putrajaya, Malaysia. But for many new and existing sky scrapers, they will still have to slum it in with drawing a significant portion of their energy needs, if not all, from the grid – which, if one tracks the power train would most likely find it fuelled, unseen from the general public, with hydrocarbons in their many forms. This is especially true for developing nations, which ironically, are rather strategically poised to re-engineer their energy mixes as they move towards a developed country status.

All this then banks the attentive reader to question the slow and cautious rate of growth in floating PV technology. If it is indeed the Holy Grail of a solar powered future especially for Oceanic countries, if it is such a ground – or in this case, water – breaking technology, why is it not in the lime light, rather than slugging it on with rates not even minutely comparable to the time when people first started to push offshore Oil and Gas technologies for seabed oil?

I can safely infer that there is no single correct answer to this; in fact, at this point, you would have your own set of opinions and the person reading this next to you may yet disagree with your intellect. Taking an educated guess, since much development is either relatively new or in Research and Development, I would imagine most investors and policy makers poised on a wait and see attitude. Because simply put, as with all new things in life, we are naturally at the very least, a bit weary of change – well, most of us, anyway – especially when it involves huge amounts of investments with uncertain rate of returns. However, it is prudent to keep in mind a-priori to passing judgement that the idea of a floating solar farm is not as farfetched as it may first seem to be when you started reading this article. The technologies for deployments of massive floating structures have been rigorously developed by the offshore Oil and Gas industry, that which has reached a certain maturity to the extent of being subsequently employed in building offshore Wind farms.

The Seasteading Institute projects that something as mind blowing as a floating city may be materialized within the next few years! So while it would be a niche to end this article by saying that offshore solar farms will too, surface into the mainstream given time, I implore you, dear reader to shift this dogma into a notion that the time is now. We are in an age where it is possible to consciously engineer our civilization into a path that is more earth-friendly – something which no other past civilization on record has - and there is really no point in delaying it any further. Opportunities abound and the time is just about right. The rest of the story, I leave to you, fellow readers to pick the next trump card and watch the rest of the world follow suit.  

 

Lee Hsiu Eik

Lee Hsiu Eik graduated from PETRONAS Institute of Technology (UTP) Malaysia with a first class honors degree in the four-year B.Eng (Hons) Civil Engineering program with a technical specialization year in offshore structures. He also holds a Master diver certification from the National Association of Underwater Instructors (NAUI) and several Technical dive specialties certification from Technical Diving International (TDI) rating him to HSE's CMAS 2 equivalent based on the United Kingdom's Health and Safety Executive List of Approved Diving Qualifications October 2012. With nearly a decade's worth of diving experience, Hsiu Eik now polls his practical sea going experience in the academia world where he operates as a Research Engineer at the Offshore Engineering Centre UTP. Aside from embarking on a range of research consultancy projects, he is actively involved in the provision of training services within the offshore engineering genre for the industry. He is also a strong proponent for a sustainable Ocean based economy with emphasis on efficient Ocean space and resources utilization.

 

 

 

The content & opinions in this article are the author’s and do not necessarily represent the views of AltEnergyMag

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