THE COASTAL WATERS surrounding Penang Island hold more than just tourist appeal and fishing potential—they could be the key to Malaysia’s renewable energy evolution. As ASEAN nations race to diversify their energy portfolios, innovative (but often ignored) technologies that leverage our most abundant resource—seawater—are emerging as promising alternatives in the renewable energy landscape. I will address two technologies here.

Seawater-activated Batteries: The Next Wave

Imagine a world where a battery doesn’t need to be charged—at least in the conventional sense, but rather, activates upon contact with seawater. This isn’t science fiction; it is a rapidly developing technology with significant implications for Malaysia’s renewable energy sector. At this juncture, it should be apparent why R&D for such tech has either been shelved or ridiculed to the hilt. Many simply avoid the simple question of why more money is not being spent developing this.

Trinasolar invested USD381.41mil in R&D, and had cumulatively filed 5,649 patent applications by the end of June 2024.[1] All that resource focused on solar cells and modules which, for all intents and purposes, are a big photosensitive diode. Doesn’t sound as sexy when you put it that way—but it is what it is. The point is that a lot of resources were thrown behind essentially proven tech to squeeze out marginal incremental improvements.

I say this to give some perspective to the effort made and the outcome achieved. Imagine the progress that could be made to develop seawater technology with the same resources and gusto.

How Do Seawater-activated Batteries Work?

This energy system typically features three key components:

• An alloyed aluminium anode

• A nickel-based cathode

• An alkaline electrolyte

When seawater enters the system, it serves as a catalyst, initiating an electrochemical reaction that generates electrical current. Unlike conventional batteries that require external charging, these systems harness the chemical potential inherent in the interaction between metals and saltwater.

For optimal performance in Malaysian coastal waters, particularly off Penang Island, the following materials show the most promise. At this juncture, we’re back to basics in terms of proven materials, purposely avoiding more exotic nano-infused materials. With that in mind, here are the everyman materials:

1. Anode Materials:

• Aluminium-magnesium-tin alloys: Offer excellent corrosion resistance while maintaining high energy density

• Aluminium-gallium-indium-tin alloys: Enhance reactivity in the tropical seawater conditions of Malaysia

2. Cathode Materials:

• Nickel-iron hydroxide: Cost-effective with good stability in warm seawater

• Manganese dioxide with carbon additives: Enhance conductivity while remaining environmentally benign

Given the scale of generation required, the anodes and cathodes would occupy a large area, and maximise energy output while maintaining cost efficiency in implementation:

1. Electrode Surface Modification:

• Increasing surface area through nano-structuring

• Implementing hierarchical porous structures to maximise reaction sites

2. Electrolyte Optimisation:

• Using ionic additives that enhance conductivity in tropical seawater temperatures

• Implementing flow-through designs that maintain fresh seawater contact

3. Material Processing:

• Mechanical alloying techniques to reduce manufacturing costs

• Utilising locally sourced materials where possible to minimise import expenses

As you can see, apart from the nano-structuring, none of what is listed is particularly high-tech.

Seawater Batteries VS. Seawater Electrolysis: Understanding The Differences

While both technologies leverage seawater, they operate on fundamentally different principles and yield different outputs. The table above seeks to clear up the crossovers, convolutions and confusion. To quote my favourite T-shirt from Thailand, “Same Same, But Different”.

Comparative Analysis

The details above are rudimentary because there simply is low/no interest in the technology given all the glamour surrounding mainstream technology, global narrative and the multi-billion-dollar ecosystem that exists.

But there is more.

Seawater-activated batteries convert chemical energy from the reaction between metals and seawater directly into electricity. This is fundamentally a one-way process where the metal anode is consumed as part of the reaction. Seawater electrolysis, conversely, requires electricity input to split water molecules into hydrogen and oxygen. When hydrogen and oxygen recombine in combustion, they produce energy and water vapour (steam).

Additionally, the electrolysis process can potentially yield freshwater and sea salt as valuable by-products if properly designed. My thoughts drift to selling bottled fresh water, giving new meaning to the term “energy drink” (see what I did there?) and “Penang’s own sea salt”.

The primary distinction lies in the direction of energy conversion:

• Batteries: Chemical energy → Electrical energy

• Electrolysis: Electrical energy → Chemical energy (stored in hydrogen) → Heat/electrical energy (when hydrogen is used)

Key Considerations For Malaysia

Blessed with coasts around nearly all of Peninsular Malaysia, Sabah and Sarawak, the appeal for the technology should be obvious to the country. However, there is always the need to weigh the pros and cons and not fool ourselves with cognitive biases. So, here is some food for thought.

Seawater-activated Battery

Advantages:

• Simple deployment makes it ideal for remote islands in East Malaysia.

• Low maintenance renders it suitable for rural coastal communities.

• No charging infrastructure is required for off-grid applications.

• Potential supplemental power source available for all coastal cities and towns.

Limitations:

• Lower power density necessitates larger deployment areas.

• Performance is affected by Malaysia’s seasonal monsoons and water temperature fluctuations.

• Shorter lifespan in tropical marine environments due to accelerated corrosion.

Seawater Electrolysis

Advantages:

• Multi-product system producing hydrogen, freshwater and sea salt aligns with Malaysia’s resource diversification goals.

• Smaller footprint makes it suitable for limited coastal industrial zones.

• Possibility of it being integrated into Malaysia’s expanding solar capacity for green hydrogen production.

Limitations:

• Higher technical complexity requires skilled workforce.

• Greater initial investment cost needed will be challenging for a developing economy.

• Electrode degradation is accelerated in tropical marine environments.

Environmental Considerations

• Both technologies have minimal environmental impact compared to fossil fuels.

• Seawater-activated battery has lower environmental impact during operation.

• Electrolysis system requires careful management of brine discharge to protect Malaysia’s rich marine ecosystems.

These estimates for seawater electrolysis and seawater-activated battery assume optimal conditions and current technological capabilities. Actual implementation would require site-specific studies considering Malaysia’s unique tropical marine environment, monsoon patterns and coastal infrastructure availability. Given that coastal areas are eco-sensitive, such a sizeable deployment might involve increasing project implementation cost into the financial “no-go” zone.

Ideal Conditions For Deployment Off Penang Island

While the technology can be implemented at numerous coastal locations, optimal implementation near Penang would feature:

• Water temperature between 28-30°C (typical for Penang’s coastal waters)

• Moderate salinity levels (approximately 32-34PSU[2])

• Protection from extreme wave action (Penang Island’s east coast)

• Proximity to existing electrical infrastructure

• Sufficient depth (10-30m) to allow for stable installation

• Minimal interference with shipping lanes and fishing activities

Specific potential deployment zones include the waters off Teluk Bahang, the northeastern coast near Batu Ferringhi or the more sheltered eastern waters near Jelutong.

While the desktop study indicates this, an actual site inspection and the preverbal environmental impact study (EIA) might say otherwise. It has never been the lack of technology that hinders progress. Given how active environmental and civil activists are in the island state, the technology for either would likely raise a few red flags; “a few” being the case because there are some people who have the ability to find a problem to every solution they’re given.

At the same time, many of us have heard this statement in one form or another, “If there’s a problem, and money can fix it... then there’s no problem.”

Such is the case with seawater-activated batteries and seawater electrolysis. If oil and gas companies can drill for oil 3km down into the murky depths in mud, sediment and megalodon remains in stormy seas, and twist their drills laterally to extract crude, how hard can it be to implement the tech discussed here?

As Malaysia continues its journey toward sustainable energy independence, harnessing the potential of the seas that surround it represents not just an environmental imperative, but an economic opportunity. With careful development and strategic implementation, seawater battery technology could become a cornerstone of Malaysia’s renewable energy portfolio, turning the azure waters of Penang into a power house of clean, sustainable energy.

FOOTNOTES

[1] https://static.trinasolar.com/eu-en/resources/newsroom/eutrinasolar-reports-revenues-6-billion-and-profits-74-million-half-yearly

[2] Practical Salinity Unit