How Heat Recovery is Baking a Greener Future



The Basics of Heat Recovery

Heat recovery in the commercial baking industry involves capturing the excess heat generated by baking ovens, particularly tunnel ovens, and repurposing it for other uses.

Typically, a large portion of the energy used in these ovens escapes into the environment as waste heat. Heat recovery systems intervene by harnessing this energy, thereby improving overall efficiency and reducing waste.

How Heat Recovery Works

Heat recovery in commercial baking is a three-step process designed to capture and repurpose waste heat from ovens, turning a potential loss into a valuable resource.

  • Capture –The journey begins with capturing the waste heat. This is primarily accomplished using heat exchangers that are installed in the oven’s exhaust system. These exchangers absorb the heat from the oven's exhaust gases – catching energy that would otherwise disappear into the atmosphere.
  • Convert – Once captured, this heat needs to be converted into a usable form. Depending on the system, this might involve heating air or water, which can then be used for various purposes within the bakery, such as space heating, water heating, or even pre-heating air for the oven itself.
  • Distribute – The final step is distributing this repurposed heat to where it’s needed most. Efficient distribution is key here – it’s all about ensuring that every bit of this recovered energy is put to good use.

Types of Heat Recovery Systems

Heat recovery in the commercial baking industry primarily falls into two broad categories – air-to-air and air-to-water systems.

Air-to-Air Heat Recovery Systems

These systems focus on capturing heat from the oven’s exhaust air and using it to heat incoming fresh air. This is particularly useful in maintaining ambient temperatures in a bakery or replacing the exhaust with pre-heated make-up air.

  • Recuperative Heat Exchangers – These devices directly transfer heat from the exhaust air to the incoming air. They are straightforward and efficient for bakeries looking to reuse heat without overly complex technology.
  • Heat Pumps – Although not a direct air-to-air system, heat pumps can be used to extract heat from exhaust air and transfer it to fresh air. They require more energy to operate but offer greater control over temperature and humidity.

Air-to-Water Heat Recovery Systems

These systems involve the transfer of heat from exhaust air or steam to water, which can then be used for various purposes in the bakery.

  • Stack Economizers – Efficiently harness the heat from exhaust gases to preheat water for various applications, such as proofers or sanitation, significantly cutting down on the energy needed for heating water.
  • Boiler Economizers – Utilize the heat from exhaust gases to preheat water entering boilers, effectively reducing the energy expenditure for steam production.
  • Heat Pumps – An air-to-water heat recovery system can be used with heat pump to incrase the return water temperature and thereby increase the supply temperature. This greatly increases the efficiency of a water-to-water heat pump.
  • Steam Recovery Systems – In bakeries using steam ovens, these systems capture the steam generated during baking and condense it back to water, which can then be reused. This type of system is highly efficient and reduces both water and energy consumption.

Customized Solutions

Depending on the specific needs and layout of a bakery, customized hybrid systems combining elements of both air-to-air and water-to-water recovery can be designed. These tailored solutions can meet specific operational requirements.

Advantages of Heat Recovery in Commercial Baking

Integrating heat recovery systems into bakery operations is a smart business strategy. From slashing energy bills to baking better products and appealing to eco-conscious customers – it's a win-win-win situation.


Energy Efficiency

The most direct advantage is a substantial boost in energy efficiency. By capturing and reusing the heat that would otherwise be lost, bakeries can dramatically reduce the amount of energy they need to operate. This streamlines energy use so that every kilowatt hour does more for the business.

Environmental Sustainability

When bakeries reduce their energy use, they're actively cutting down on greenhouse gas emissions. This move towards more sustainable operations isn't just a win for the environment – it also strikes a chord with consumers who value eco-friendly practices.

Plus, by embracing these greener methods, bakeries can stay ahead of the curve with environmental regulations, sidestepping potential fines and setting a standard for responsible business practices.

Cost Savings

Investing in a heat recovery system might seem like a significant investment upfront, but the financial upside in the long run is pretty compelling. By reducing energy costs, these systems often pay for themselves over time. For forward-thinking bakeries, it's a smart move – especially with energy prices on the rise.

Enhanced Process Control

This benefit is often overlooked but is key in this industry. Heat recovery systems can offer more consistent and controlled heating or drying conditions which can lead to a noticeable improvement in product quality – think perfectly baked goods every time. This level of control can also help in reducing product wastage due to uneven baking.

The Challenges of Heat Recovery

While the adoption of heat recovery systems in commercial baking presents clear benefits, bakeries may still have concerns about practical and technical challenges.


Technical Complexity

The installation of heat recovery systems involves a significant level of technical complexity. The real trick is in integrating these systems flawlessly, preferably while the ovens are already in use. It's about finding that sweet spot where the system effectively recaptures heat without meddling with the oven's core functions or the baking process itself. This requires a nuanced understanding of both the existing oven technology and the intricacies of heat recovery systems, making it essential to involve experts who can tailor the installation to meet specific bakery needs.

Initial Investment and ROI Calculation

A major consideration for bakeries eyeing heat recovery systems is the initial financial outlay. It's not just about affording the setup – there's also the task of calculating the return on investment (ROI). This calculation is unique to each business as it depends on the bakery's size, the fluctuating energy market, and the specific efficiency of the installed system.

Maintenance and Operational Integration

Like any other piece of equipment, heat recovery systems demand consistent upkeep to perform optimally, which brings us to a significant concern for bakeries – the risk of downtime. Regular maintenance tasks like cleaning, component checks, and troubleshooting are necessary but can interrupt the continuous flow of a bustling bakery. For bakeries, where time is literally money and production schedules are tight, even a small amount of downtime can lead to significant losses and disrupt order fulfillment. This concern puts a spotlight on the heat recovery equipment and the need for a maintenance plan that minimizes disruption.

Space Constraints

Many commercial bakeries operate in limited space, making the integration of additional equipment challenging. Heat recovery systems, depending on their design and the size of the bakery, can require significant space, which might not be readily available. Some heat recovery systems offer flexibility in terms of location and can be installed indoors or outdoors on a roof, next to a building, or where space is less tight.

Need for Consistent Baking Quality

Consistency is king in the baking world. The introduction of a heat recovery system must not upset the delicate balance of temperature and humidity that's essential for perfect baking results. This means the system needs to be finely tuned and monitored closely to maintain a stable environment inside the oven. Any deviation could lead to inconsistencies in product quality, which is a major concern for bakeries that pride themselves on the uniform excellence of their products.

Compliance with Regulations

As with any major equipment installation in a food production facility, bakeries must ensure that their heat recovery systems comply with all relevant health, safety, and environmental regulations. Navigating these regulations and ensuring compliance can be complex and time-consuming.

Adapting to Different Oven Types and Sizes

Bakeries use a wide range of ovens, each with its own set of characteristics. A heat recovery system suitable for one type of oven might not be as effective or even feasible for another. Tailoring these systems to work effectively across the spectrum – from the compact convection ovens of a small patisserie to the massive tunnel ovens of a commercial bakery – requires both ingenuity and technical finesse.

Heat Recovery and the RHX System

Heat recovery systems have made waves in the baking world – turning the heat efficiency game on its head for tunnel ovens. By snagging and reusing heat that would typically just vanish, bakeries are seeing real drops in both their carbon emissions and energy bills. However, downtime, investment costs, and integration difficulties remain a concern for bakeries.


The RHX Roof-Top Heat Exchanger System from ENERVEX provides a solution to these concerns while harnessing the full potential of heat recovery.

  • Minimal Downtime – The installation process is designed for minimal disruption, often requiring less than 30 minutes of operational downtime for your ovens. This quick setup primarily involves fitting a special chimney Tee section with an integration bypass damper. Once the heat recovery unit is operational, the bypass damper is closed, allowing exhaust to pass through the heat modules for efficient air-to-water heat transfer. Installations can take less than 30 minutes of downtime.
  • Turnkey Solution – The RHX system is a complete heat recovery unit (HRU) that includes heat exchanger modules, dampers, plumbing, and controls. All the bakery needs to supply are utilities, supply and return pipes, and power.
  • Easy Maintenance – With features like the integrated by-pass and the removable heat modules easily accessible through access panels, the RHX system can be serviced and maintained without any downtime.
  • Customization and Flexibility – Adaptable to various bakery needs, the RHX system can be customized to different oven types and sizes.
  • Durability – Made with stainless steel and skid-mounted for roof installation, it's built for long-term efficiency and ease of service.
  • Quality Assurance – The system’s precise controls ensure that heat recovery does not impact baking quality, maintaining product consistency.

If you’d like to discover the power of the RHX Roof-Top Heat Exchanger System from ENERVEX – Contact us today to learn more!