We live on a planet ripe with natural resources, a self-sustaining world with organically functioning ecosystems benefitting all lifeforms. It’s said that we know more about outer space than we do about our own oceans; we haven’t even begun to scratch the surface of what exists deep in the sea that covers most of our planet. 

As technology has advanced, we have managed to explore further and deeper all around the world. One of the most impressive feats has been the exploration of the Clarion-Clipperton Zone, the oceanic space between Mexico and Hawaii that is nearly the size of Europe. Scientists have explored as far down as three miles, leading to the discovery of many new species and sediments that could help our energy storage challenge.

Small, polymetallic nodules have been discovered — palm-sized rocks that have built up metals over millions of years, growing incredibly slowly and sustaining a large part of the ecosystem around them. Through scientific study, it’s been realized that these rocks sustain what is considered a battery, as its metals could provide organic energy and supply needed power.

However, detrimental effects come with using these nodules. A recently discovered ecosystem of hundreds of species relies heavily on these nodules and would be significantly affected if they were removed. 

One of the primary arguments against deep-sea mining is its potential to cause severe and irreversible damage to unique and fragile deep-sea ecosystems. The deep ocean is a biodiverse environment with many species yet to be discovered, and mining activities could lead to the loss of biodiversity, habitat destruction and disturbance of deep-sea communities. 

According to Mining Technology, a report suggests that deep-sea mining could result in up to 25 times more damage to biodiversity than land-based mining, translating into $500 billion of lost value (https://bit.ly/4eZvP5T).

So, what do we do? We can continue mining for these nodules or consider the alternative: gather electricity storage — such as the battery power found in the nodules — without disrupting entire ecosystems and requiring such massive funding. 

Thermal Heat Transfer 

On the opposite end of things, the sun can give us thermal energy, reducing the need for precious metals found in these polymetallic nodules. When considering solar collectors, there are two kinds: thermal energy (hot water) and photovoltaic (PV).

For starters, a PV panel absorbs solar energy and turns it into direct current (DC) electricity. That is sent through inverters that convert the DC electricity to alternating current, making it usable for homes and commercial-sized buildings. Due to such a surplus of solar PV energy during daylight hours, battery storage has become an essential technology to distribute that energy in the evening when the sun is no longer shining. 

With a solar thermal panel, the thermal energy must also be reserved for use during the evening hours. Thermal energy can be stored in holding tanks. Further, new technologies involving phase-change materials can supply greater thermal storage with less volume. 

The Solar Authority notes that, on average, a PV collector converts approximately 12 percent of the sunlight into electrical energy (https://bit.ly/403rsT9). The energy obtainable from the sun is about 1kW per square meter. 

“This translates to roughly 3,400 [BTU/hour/square meter],” the company says. “With a 70 percent [conversion rate] using a solar-thermal collector, we need about 42 square meters (450 square feet) to yield as much warmth as a typical home’s gas furnace (100,000 BTU/hour).” 

Solar thermal panels only cost about 20 percent of what PV panels cost per square foot. When you combine six times the efficiency with five times better pricing, you get something that is 30 times more effective in principle.

The Solar Authority notes that electrical storage is more prevalent to most people due to the demand for electricity in about any functioning building (https://bit.ly/403rsT9). Many people don’t realize that their hot water tank is thermal energy storage for any hot water needs in buildings. 

Solar thermal efficiency is higher than PV’s; you can extract roughly 70 percent of the sun’s energy with a solar thermal collector by circulating heat transfer fluid through it. In simple terms, you can capture thermal energy when the sun shines and use heat transfer fluid to pull a large percentage of that energy for use. 

So, the need for deep-sea mining is less urgent than it may be presented to be. We have so many resources available that don’t involve disrupting important ecosystems and spending billions of dollars that could go toward other important efforts. 

Energy is all around us: the sun, the earth and the myriad of technological advances we’re constantly developing. We can use what we have; we don’t need to look deeper when we’re already surrounded by solutions.