High-Density Renewable Thermal Systems Transforming Industrial Process Heating in Food Manufacturing
The cost of thermal energy has become a critical factor influencing the profitability of food processing industries specialising in sauces and vegetables. These facilities rely heavily on continuous thermal processes operating between 60 and 220 degrees Celsius, including sterilisation, concentration, pasteurisation, and cleaning. The volatility of gas prices, stricter emission regulations, and increasing transparency demands from consumers are compelling industry players to seek more cost-effective and sustainable heating options.
In this context, the discussion has shifted from simply adopting renewable energy to evaluating the true economic value of various solutions. The focus now lies on the real cost per Megawatt-hour of thermal energy and how effectively available space can be utilised to maximise energy output. Energy density, measured in Megawatt-hours produced per square metre, is emerging as the primary indicator of competitiveness for renewable heat in industrial applications.
Across Spain and Europe, industries with high thermal demands are demonstrating that solar thermal systems with high energy density and storage can deliver renewable industrial heat at a significantly lower cost. Supported by government incentives and long system lifespans, these systems are proving to be a viable alternative to fossil fuel-based heating. This transition is especially feasible in regions like Spain, where solar availability and density of thermal energy per unit area are among the highest in Europe.
The real game-changer is the realisable cost reduction, expressed in euros per square metre installed, which directly correlates to lower costs per Megawatt-hour of thermal energy. Modern projects assess efficiency based on how much usable energy can be generated from a given surface area, reducing capital expenses, improving return on investment, and optimising land or roof space near processing facilities. Since the thermal demand in these industries remains stable all year round, renewable systems with thermal storage can offer a cost-competitive, reliable heating source, outpacing traditional gas solutions under current subsidy schemes.
Many thermal processes involved in sauce and vegetable processing require high-temperature steam, often between 170 and 220 degrees Celsius. These include sterilisation, evaporation, and cleaning processes, which can account for up to 65% of total energy consumption in some plants. Therefore, reducing the cost of thermal energy can have a direct impact on operational margins and environmental sustainability.
Spains favourable solar conditions, combined with increasing costs of fossil fuels and carbon pricing, are making solar thermal systems with thermal storage an economically attractive option. They enable plants to produce a significant share of their thermal energy in-house, reducing dependency on fossil fuels and stabilising operational costs over the long term. For plants operating within specific temperature ranges where solar thermal can be optimally utilised, reductions in thermal energy costs of 30 to 50% are achievable without altering production recipes or product quality.
The primary advantage derives from the predictability and stability of renewable thermal energy. In contrast to volatile fossil fuel markets, renewable systems with thermal storage deliver a consistent, controllable heat supply. This capability allows processors to lock-in long-term cost estimates, enhance financial planning, and mitigate risks linked to supply disruptions, geopolitical tensions, and carbon pricing policies.
Supported by subsidy programmes such as Spains PERTE, regional incentives, and the EU Innovation Fund, projects integrating solar thermal with storage can realise short payback periods of four to five years. Once investments are recovered, the operational costs mainly involve maintenance, further enhancing economic viability.
As an illustrative case, a medium-sized sauce and vegetable processor in southern Spain invested in a solar thermal system with high energy density, directly integrated into the plants existing steam network. The system, comprising approximately 250 high-efficiency collectors and thermal storage tanks, supplies around 4100 MWh annually, covering nearly 41% of the plants demand. The total investment, after subsidies, was around 1.36 million euros, with a payback period of less than five years, and significantly lowered CO2 emissions. This real-world example underscores how optimising space and leveraging available solar resources can transform industry-standard practices.
From pilot projects to standard industrial practice, high-density renewable thermal systems are now delivering lower-cost, reliable, and cleaner heat sources for food processing plants. They enable industries to achieve regulatory compliance, pursue ESG targets, and ensure energy independence over the long term. As they become more widespread, these solutions will be crucial for the ongoing transition towards sustainable industrial operations. Processors are encouraged to evaluate their thermal profiles, assess potential savings, and explore available incentives to adopt these innovative systems proactively.