In part one of this series, I explored how we're rethinking sources of ocean energy — from thermal gradients to nuclear SMRs to currents. But understanding energy in the ocean means looking at both sides of the equation. This time, I want to talk about uses: where energy is being consumed in ocean and coastal environments today, where demand is shifting, and where new opportunities are emerging. Because reimagining energy infrastructure only matters if it maps to real demand. And in the ocean, that demand is not only changing — it’s being reshaped by concerns about energy security and shifting cost curves.
Where Energy Gets Used at Sea
Historically, energy in the ocean has been synonymous with combustion (sorry sailors) — think diesel engines and bunker fuel, powering everything from cargo ships to fish farms to ports. It’s mobile, dense, and cheap — and that’s been enough to dominate ocean and coastal operations for the last century. But now that’s changing. Today, ocean and coastal energy demand shows up in five big buckets:
- Maritime shipping – propulsion, fuel transitions, hotel power, refrigeration, ballast systems, hull maintenance, and much more
- Port and coastal operations – port electrification, drayage, workboats, shipyards, cold storage, data centers, mobile power, and much more
- Aquaculture and offshore industry – pumps, aeration, surveillance, feeding
- Data demand – autonomous vessels, sensors, data buoys, catastrophe monitoring, IOT
- Military and defense – autonomous systems, forward-operating bases, covert ops
What’s common across these sectors is a growing vulnerability: reliance on liquid fossil fuels that are becoming more expensive, have unclear long-term procurement trajectories, and are less aligned with operational and regulatory expectations.
Energy Security as a Strategic Imperative
Energy security is fast becoming a central concern in maritime and coastal industries — and not just in the geopolitical sense. Operators across sectors are facing a triple squeeze:
- Volatility and long-term uncertainty on fuel prices and availability
- Supply chain disruptions
- Increased scrutiny and regulation on maritime emissions (IMO MEPC83, EU ETS)
For many, fuel is no longer just a commodity — it’s a strategic liability. The risk of not being able to secure or afford reliable fuel has become a board-level issue. And the exposure to regulations and fines targeting decarbonization is compressing margin. And for forward-looking operators, the question is now: What can I electrify? What can I localize? What can I decouple from global fuel volatility? Energy security is not just about defense. It's about enabling operational continuity, resilience in remote environments, and predictable OPEX in a decarbonizing world. This shift opens the door to startups that can offer clean energy alternatives that are reliable, modular, and defensible — even if they aren’t the absolute cheapest per kilowatt-hour today.
Rethinking Energy Use at the Edge
The ocean is full of “last-mile” energy challenges — remote locations, moving platforms, and distributed infrastructure. Electrification isn’t always possible, but where it is, it’s often underserved. Where it’s not, there may be opportunities for fuel switching, waste heat recovery, or system-level efficiency gains. A few key questions guide how we think about innovation on the demand side:
- Where can we electrify systems currently running on combustion? How do we chase the cheaper MWh?
- Where is energy being wasted or used inefficiently? And what solutions can prevent system failures?
- Where are customers already paying a premium for reliability or resilience?
- Where can we provide new energy vectors (e-fuels, green hydrogen, nuclear) in settings that value density and modularity? How do we create markets instead of disrupt?
These questions are no longer theoretical — they’re economic and strategic imperatives. And they create investable white space for startups that solve not only for performance, but for supply chain independence and cost: present or future.
Where Efficiency Meets Opportunity — Portfolio Examples
Vema: the feedstock is the problem
Vema is pioneering a novel approach to stimulate hydrogen from abundant rock formations. The impact could be the lowest cost of delivered hydrogen. We spent years looking for green maritime fuel companies-and were hung up on cost time and again. Cheap hydrogen feedstock is a key unlock, and Vema may have cracked it.
Calcarea: most assets still need carbon capture
Calcarea has built a novel system for onboard carbon capture and storage at sea for the maritime sector, enabling avoided emissions and safe, permanent storage of CO2. As shipping companies consider how to meet new IMO regulations to decarbonize their long-term assets, Calcarea is introducing a new use case that doesn’t require retiring or dramatically retrofitting a ship.
Indeximate: efficiency and preventative maintenance
Indeximate has a software solution for delivering real-time monitoring for subsea energy cables. Subsea energy cables are both expensive to install and insure, and when they fail they take awhile to repair and the lost energy must find an often-expensive substitute. Fixing them before they break is a massive cost-saver.
The Horizon: Future Uses Worth Building For
As we look ahead, we’re excited by a wave of new demand profiles emerging in ocean sectors — where premium energy applications will justify new supply chains:
- New energy sources for maritime vessels: nuclear-powered for military and commercial maritime purposes; wind-augmented propulsion; e-fuels, alt-fuels and bio-fuels; electrified hotel power and much more.
- kWh scale picks and shovels for remote deployment: there are going to be a lot more “things” in the ocean in the coming decades that need power: Think of use cases to: drive demand for ocean/climate data, as global militaries adapt to drone-ified warfare at sea, as climate changes shift how we operate at the coastline and in new parts of the sea.
- Forward-deployed energy nodes: to support defense, disaster response, and sovereign monitoring. The same as batteries are scaling everywhere alongside rapid energy generation (SO many LNG turbines being bought); that trend will replicate for forward-deployment at home and abroad.
- Re-envisioning coastal infrastructure: ports, coastal assets, riverine transport, shifting small island nation strategies, all of these places have new energy frontiers.
Each of these reflects a sector where energy security, cost control, and carbon accountability are converging — and where traditional energy solutions fall short.
The Takeaway: Match Energy Innovation to Real Ocean Demand
There’s a reason diesel has dominated the ocean economy for a century: it works, it’s cheap, and it’s flexible. But it’s also dirty, inefficient, and increasingly fragile in the face of market and regulatory shocks (cough, cough, tariffs). The next generation of ocean energy companies will succeed not by replacing diesel everywhere, but by matching clean, modular, or intelligent energy solutions to specific edge use cases — the hatchery, the buoy, the forward-operating base.
For founders: Think hard about energy demand — not just generation. The market isn’t always in the watt. Sometimes it’s in the efficiency, the autonomy, or the fuel switch. And increasingly, it's in the ability to secure, bunker, store, and deploy energy with confidence.
The future of ocean energy isn’t just about how we generate it. It’s about how — and where — we use it, and whether we can count on it to be there.