The cheapest renewable energy source today is solar power, specifically utility-scale solar photovoltaic (PV). In many parts of the world, solar has become the lowest-cost source of new electricity generation, often beating both fossil fuels and other renewables on price. But for industrial companies, “cheapest electricity” and “cheapest energy for your process” are two very different questions—and that gap matters enormously when you are trying to decarbonize heat.
Cheap renewable electricity does not automatically mean cheap decarbonized heat
Most conversations about renewable energy costs focus on electricity generation. That makes sense for power grids and consumer energy, but industry runs on heat—and converting cheap renewable electricity into high-temperature industrial heat is expensive, inefficient, or simply not yet feasible at scale. Companies that assume the falling cost of solar or wind will solve their industrial heat problem often discover that electrification requires major infrastructure upgrades, grid capacity that is not available, or capital investment that makes the business case fall apart. The practical fix is to evaluate energy costs not at the meter, but at the point of use—accounting for conversion losses, infrastructure, and process compatibility.
Sticking with fossil fuels while waiting for a cheaper solution is a risk, not a strategy
Every year a company delays decarbonizing its heat, it accumulates carbon costs, regulatory exposure, and reputational risk. EU Emissions Trading System prices, tightening Scope 1 reporting requirements, and customer expectations are all moving in one direction. The assumption that a cheaper or easier solution is just around the corner has a real cost—not just in emissions, but in competitive positioning and long-term asset value. The more productive question is not “what is cheapest in theory?” but “what is cost-competitive and deployable now?”
What is the cheapest renewable energy source today?
Solar PV is currently the cheapest renewable energy source for electricity generation. In regions with strong sunlight, the cost of generating solar electricity has dropped dramatically over the past decade, making it competitive with—and often cheaper than—coal and gas. Onshore wind is the second most cost-competitive option in many markets.
These cost reductions are real and significant. The price of solar panels has fallen by more than 90% since 2010, driven by manufacturing scale, improved technology, and competitive global supply chains. Onshore wind has followed a similar trajectory. Both technologies now represent the lowest-cost options for adding new electricity capacity in most parts of the world.
Other renewable sources—offshore wind, hydropower, geothermal, biomass—vary considerably in cost depending on geography, resource availability, and infrastructure requirements. They remain important parts of the energy mix, but none consistently match the cost levels that solar and onshore wind have reached in favorable locations.
How are renewable energy costs measured and compared?
Renewable energy costs are most commonly measured using the Levelized Cost of Energy (LCOE). LCOE calculates the total cost of building and operating an energy system over its lifetime, divided by the total energy it produces. This gives a standardized cost per unit of energy—typically expressed in euros or dollars per megawatt-hour—that allows fair comparison across different technologies.
LCOE is useful but has limitations. It captures the cost of generating energy at the source, not the cost of delivering it to where it is needed, storing it, or converting it into the form a specific process requires. For electricity, this means LCOE does not reflect grid connection costs, transmission losses, or the cost of backup capacity when the sun is not shining or the wind is not blowing.
For industrial heat specifically, LCOE becomes even less informative. A company that needs steam at 200°C or process heat above 1,000°C cannot simply plug in a solar panel. The relevant cost metric is the delivered cost of heat at the point of use—accounting for fuel cost, conversion efficiency, infrastructure investment, and operational reliability. That number looks very different from a headline LCOE figure.
Which renewable energy source is cheapest for industrial heat?
For industrial heat, no single renewable source dominates on cost. The answer depends on temperature requirements, site conditions, and available infrastructure. Biomass, geothermal, and solar thermal can work at lower temperatures. For high-temperature processes above 500°C, options narrow significantly—and cost comparisons shift toward delivered heat cost rather than raw generation cost.
High-temperature industrial heat—the kind needed in food processing, specialty chemicals, and pulp and paper production—is one of the hardest parts of the energy system to decarbonize. Most renewable electricity sources can generate heat through electric resistance or heat pumps, but efficiency drops sharply at higher temperatures, and the infrastructure costs are substantial.
Emerging technologies like iron fuel are designed specifically to address this gap. Iron powder burns at temperatures up to 2,000°C, producing high-temperature heat with zero direct CO₂ emissions. The Iron Fuel Boiler achieves up to 95% energy efficiency—a strong performance figure for any industrial heat system. You can read more about how the technology works on our Iron Fuel Technology page.
Why is cheap renewable electricity not always the answer for industry?
Cheap renewable electricity does not automatically translate into affordable industrial heat because of conversion losses, infrastructure requirements, and process constraints. Electrifying high-temperature heat demands either electric resistance heating—which is energy-intensive—or heat pumps, which lose efficiency above roughly 150°C. For many industrial processes, neither option is technically or financially viable today.
Beyond the technology limitations, there is the infrastructure question. Many industrial sites are not connected to grids capable of handling the electrical load that full electrification would require. Upgrading grid connections takes years and costs millions. For a company facing near-term emissions targets, waiting for grid infrastructure is not a realistic plan.
Hydrogen is another option that gets significant attention, but it faces its own barriers. Green hydrogen remains expensive, supply chains are still developing, and burning hydrogen requires significant modifications to existing boiler systems. For companies that need a practical, deployable solution now, hydrogen often does not fit the timeline or the budget.
What makes iron fuel a cost-competitive option for industrial heat?
Iron fuel is cost-competitive because it is priced to align with fossil fuel alternatives, integrates with existing boiler infrastructure, and delivers zero direct CO₂ emissions without requiring a complete system overhaul. The fuel is priced at around 140 euros per tonne, and the boiler system investment is approximately 0.5 million euros per megawatt thermal—a manageable entry point for industrial operators.
The circular nature of the technology also supports long-term cost stability. Iron powder burns to produce iron oxide, which is then regenerated into iron fuel using low-carbon hydrogen. This closed loop means the material is reused rather than consumed, reducing dependence on raw material supply chains. Long-term fuel supply contracts provide further price predictability—something fossil fuel buyers rarely enjoy.
From an emissions perspective, iron fuel combustion produces near-zero CO₂. The only carbon output comes from a small pilot safety flame, resulting in just 10 kg of CO₂ per megawatt-hour of thermal energy. For companies calculating their Scope 1 footprint and facing carbon pricing, that difference relative to gas or coal has a direct financial value that belongs in any honest cost comparison.
How should industrial companies choose a renewable heat source?
Industrial companies should choose a renewable heat source by evaluating four factors: the temperature requirements of their process, the delivered cost of heat at the point of use, compatibility with existing infrastructure, and supply reliability. A technology that looks cheap on paper but requires years of infrastructure investment or cannot reach the required process temperature is not a practical option.
A structured evaluation process helps avoid costly mistakes. Consider working through these steps:
- Map your heat demand—identify the temperature ranges, volumes, and timing of your heat requirements across all processes.
- Assess your infrastructure—evaluate grid capacity, site layout, and what modifications each technology option would require.
- Calculate delivered cost—go beyond generation cost and include fuel supply, conversion efficiency, capital investment, and carbon pricing exposure.
- Check supply reliability—understand whether the fuel or energy source can be guaranteed at the volumes and consistency your operations require.
- Evaluate regulatory fit—confirm how each option performs against your Scope 1 reporting obligations and any applicable carbon pricing mechanisms.
The goal is not to find the cheapest energy source in isolation, but the most cost-effective path to decarbonized heat that works within your operational and financial constraints. That assessment will look different for a food processor with continuous steam demand than for a specialty chemicals plant with batch-processing needs.
Exploring what other industrial companies in your sector are doing can also sharpen your thinking. Our solutions overview gives a practical picture of how iron fuel fits into real industrial settings.
How RIFT helps industrial companies decarbonize their heat
We built Iron Fuel Technology specifically to address the challenge this article describes: high-temperature industrial heat that is genuinely hard to decarbonize with conventional renewable options. Here is what we offer:
- Zero direct CO₂ combustion—our Iron Fuel Boiler produces high-temperature heat with near-zero carbon emissions and ultra-low NOₓ output.
- Drop-in compatibility—the system integrates with existing boiler infrastructure, so you avoid the cost and disruption of a full system replacement.
- Cost-competitive pricing—iron fuel is priced to align with fossil fuel alternatives, making the business case straightforward.
- Reliable fuel supply—long-term supply contracts give you the certainty you need to plan ahead and meet your emissions targets.
- 95% energy efficiency—our boiler system performs at a level that compares favorably with most existing industrial heat systems.
If you are evaluating your options for industrial heat decarbonization and want to understand whether iron fuel fits your situation, get in touch with our team for a direct conversation.