Renewable Energy Sources That Are Not Quite There Yet
As the world moves rapidly toward reducing carbon emissions and tackling climate change, the push for renewable energy has never been stronger. Wind, solar, and hydropower have already proven themselves to be viable alternatives to fossil fuels in many parts of the world. However, not all renewable energy sources are created equal—some are still in the early stages of development, facing technical, economic, or logistical challenges that prevent them from being widely adopted or commercially viable.
While innovation continues at a breakneck pace, certain renewable energy technologies—though filled with potential—are not quite there yet. This article explores five such renewable energy sources that are exciting but still need time, investment, and breakthroughs before they can make a significant impact on our energy future.
1. Solar Fabric: Energy-Generating Textiles
What is it?
Solar fabric is a form of photovoltaic textile—essentially, fabric woven with solar cells or coated with photovoltaic materials. Imagine tents that charge your devices, awnings that power your home, or even clothing that generates electricity as you walk in the sun.
Why it’s promising:
The idea of integrating solar power into everyday materials opens a world of possibilities. Portable, lightweight, and flexible, solar fabric could provide decentralized energy to remote areas, soldiers in the field, or campers in the wild. It has the potential to make any surface a power-generating one, without the need for rigid panels.
Challenges:
Despite its potential, solar fabric remains largely experimental. Efficiency is a major concern; most solar fabrics have a conversion efficiency of just a few percent, significantly lower than traditional silicon-based solar panels, which regularly reach 20-25%.
Moreover, durability and cost are big hurdles. Textiles need to withstand repeated folding, weather exposure, and mechanical stress—conditions under which current photovoltaic materials degrade quickly. Integrating solar capabilities into fabrics also increases manufacturing complexity and costs, making widespread commercial adoption a distant prospect.
Current status:
Startups and research labs around the world are working on prototypes, and some consumer products (like solar backpacks) exist, but these are novelty items rather than scalable solutions. Until significant improvements are made in efficiency, durability, and cost, solar fabric will remain a niche technology.
2. Algae Biofuel: Nature’s Oil Factory
What is it?
Algae biofuel is produced from various strains of algae that naturally produce oils. These oils can be processed into biodiesel or other forms of renewable fuel. Unlike other biofuels (like corn ethanol), algae can be grown on non-arable land and with non-potable water, making it an environmentally friendly option.
Why it’s promising:
Algae can potentially yield 10 to 100 times more fuel per acre than traditional biofuel crops. They also absorb carbon dioxide as they grow and can be cultivated in wastewater, turning two problems into one elegant solution.
Challenges:
Despite its environmental benefits, algae biofuel has struggled with high production costs. Growing, harvesting, and processing algae into fuel remains expensive and energy-intensive. Large-scale cultivation also faces technical issues such as maintaining ideal growth conditions and preventing contamination.
Another significant hurdle is scalability. To replace even a fraction of fossil fuels, algae would need to be grown on a massive scale, which requires significant infrastructure and water use—despite its ability to use non-potable water, managing and distributing that at scale is no small feat.
Current status:
Several companies, including ExxonMobil, have invested in algae biofuel research, but most have scaled back their ambitions due to the slow progress and high costs. For now, algae biofuel remains more of a laboratory curiosity than a mainstream fuel alternative.
3. Tidal and Wave Energy: Power from the Ocean
What is it?
Tidal and wave energy systems harness the natural movement of ocean waters—through rising tides or surface waves—to generate electricity. Unlike solar or wind, ocean-based energy sources are incredibly predictable and consistent.
Why it’s promising:
The ocean is a vast, untapped source of renewable energy. Tides are governed by the moon’s gravitational pull, making them highly reliable. Wave energy also has immense global potential, especially in coastal regions where demand for power is high.
Challenges:
The main issue is engineering. Ocean environments are harsh—saltwater corrodes equipment, and storms can destroy fragile installations. Maintenance is costly and difficult, especially for offshore systems.
There are also environmental concerns, including potential impacts on marine life and habitats. In addition, tidal barrages (which function like underwater dams) can affect local ecosystems and sediment flow.
Financial viability is another barrier. Building and installing underwater turbines or floating platforms requires heavy upfront investment, and the levelized cost of energy (LCOE) for tidal and wave energy remains significantly higher than solar and wind.
Current status:
A number of pilot projects have demonstrated the feasibility of tidal and wave power, such as the MeyGen tidal array in Scotland. However, few have reached commercial-scale deployment. Until costs come down and technology becomes more robust, ocean energy will remain a supplemental source rather than a primary one.
4. Space-Based Solar Power: Beaming Energy from Orbit
What is it?
Space-based solar power (SBSP) involves placing solar collectors in orbit, where they can capture sunlight without atmospheric interference, and beam the energy back to Earth using microwaves or lasers.
Why it’s promising:
In space, solar panels receive uninterrupted sunlight 24/7, vastly increasing their efficiency. An orbital solar array could provide constant, global power—ideal for both civilian and military applications. It could also offer energy independence to remote or underserved areas.
Challenges:
This concept faces enormous technical and financial obstacles. Launching large solar arrays into orbit is currently prohibitively expensive. Beaming power back safely and efficiently is another issue; converting solar energy into microwaves or lasers and then back into electricity introduces conversion losses and safety concerns.
Additionally, space debris and the need for extremely precise alignment complicate the deployment of large orbital platforms. Any malfunction or collision could have catastrophic consequences.
Current status:
Organizations like the Japan Aerospace Exploration Agency (JAXA), China’s CNSA, and NASA have conducted studies and small-scale tests. In 2023, a team at Caltech successfully launched a prototype satellite capable of wireless power transfer. But commercial SBSP is likely decades away from being viable.
5. Enhanced Geothermal Systems (EGS): Tapping the Earth’s Heat
What is it?
While traditional geothermal systems rely on naturally occurring hot water reservoirs, Enhanced Geothermal Systems (EGS) involve drilling deep into the Earth and injecting water into hot dry rock to create a geothermal reservoir.
Why it’s promising:
EGS dramatically expands the potential reach of geothermal energy. Instead of being limited to regions with natural geothermal activity, EGS could make baseload, renewable power available almost anywhere. It also produces minimal emissions and occupies a small land footprint.
Challenges:
EGS is a high-risk, high-reward proposition. Drilling miles underground is extremely expensive and technologically demanding. There are also concerns about induced seismicity—earthquakes triggered by the injection of water into rock formations.
In addition, controlling the underground reservoir over time is difficult. Ensuring the rock stays permeable and that water circulates efficiently through the system requires advanced monitoring and engineering.
Current status:
The U.S. Department of Energy and other international agencies are funding EGS pilot projects, such as the FORGE initiative in Utah. While the technology is progressing, it’s not yet commercially competitive with other renewable sources. If breakthroughs in drilling and reservoir management occur, EGS could become a major player.
Hope on the Horizon, but Not Yet in the Grid
The global transition to clean energy is well underway, but not all renewable technologies are ready for prime time. Solar fabric, algae biofuel, tidal and wave energy, space-based solar, and enhanced geothermal systems all offer tantalizing possibilities—but each is hampered by technical, financial, or ecological challenges that must be overcome before they can contribute meaningfully to our energy mix.
That doesn’t mean these technologies should be written off. On the contrary, continued investment in research, pilot projects, and infrastructure is crucial. As we’ve seen with wind and solar power, what was once expensive and impractical can become commonplace with enough innovation and time.
In the race toward a decarbonized future, it’s not just about scaling up existing solutions—it’s also about preparing for the next wave of breakthroughs. The future of energy will be diverse, distributed, and dynamic. These “not-quite-there” technologies might just be tomorrow’s game-changers.