Hydronics have been around for a very long time, and when we talk about their lifecycle, availability and sustainability, we’re looking at a proven track record of hydronic system equipment lasting 20 to 30 years or even longer. In fact, we have customers frequently reaching out to us for replacement parts for systems that have been in service for three to four decades. So, when looking at the initial investment, VRF systems can certainly be attractive, especially in smaller systems. However, when you move to large-scale buildings – the kind that are often in metropolitan areas utilizing more equipment with longer run times – the total cost of ownership over the life of a VRF system should be considered. When looking at the longevity of VRF systems – say, over a 20-year period – it is likely that you may have already replaced the system, which doubles your spending when compared to more durable hydronic systems. Yet, the decision between a hydronic system and VRF is not solely about economics. From a health and safety perspective, it's certainly riskier to run refrigerant through your entire building versus running water.

When you refer to runs in an office building, you’re talking about ductwork right? And how it’s not a necessary component of hydronic systems?

While you’ve got different options depending on if it’s a heating or cooling system, when it comes to transferring heat across large spaces, there's simply no comparison between air and water. The heat-carrying capacity of water versus air is about 3,500 times greater in terms of British thermal units. As a unique substance on earth, there are certain things water is really good at, and thermal transfer is one of them. This is why it’s so important to leverage the efficiency of water in hydronic systems. If you're trying to run ductwork over long distances and carry thermal energy with air, it can become very expensive and there are a lot of other losses to consider as well.

Could you delve into how carbon footprints compare, and how they’re calculated more generally?

Carbon footprint is a big part of this story. Many different things are at play, including equipment disposal and the actual energy efficiency of the chosen solution. This is where the benefits of hydronics become clear because of its long equipment lifespan and considering that it’s technology that is age-old compared to a lot of other things. Plus, as I mentioned before, the energy efficiency associated with water is prevalent in heat transfer applications, but also in its ability to precisely control temperature in different heating and cooling zones. Efficiency and reliability are really the name of the game for environmental impact. 

Then energy storage is another aspect to these systems. Lack of energy storage pushes the grid, but this can help commercial buildings be part of the solution, right?

We’re confronting extreme temperatures and a strained, aging grid system across the United States. While there are some great ambitions to electrify various sectors and reduce reliance on fossil fuels, the reality is that our infrastructure isn’t prepared to meet efficiency goals that require substantial investments. Rather than only focusing on expanding electrical capacity, we have to be reasonable about what energy we're using and figure out ways to reduce demand, especially during peak periods. Hydronics is well poised for that in leveraging water’s strong thermal storage properties. Storing energy in a thermal space, which is easy to do, eliminates the need for conversion to electricity. That stored thermal energy can then be used to heat a building. 

As you can see, there are great capabilities built into hydronics, especially for those buildings or commercial building owners with existing hydronic systems. Once you have a hydronic system in place, you know that how you connect it and how you heat it has a tremendous amount of flexibility as we go forward with new and creative renewable energy sources. What’s most exciting, though, is the ability to enhance decarbonization efforts without undertaking massive building overhauls. Picture this: removing an old boiler and installing an electric heat pump or establishing a connection to a geothermal system, all without the need to reconfigure the entire building. With the zoning structure and established transport system in place, hydronics serve as a reliable foundation for future energy transfer endeavors. It’s the ability to say, “Okay, I already have a hydronic building, but I can decarbonize more.”

Can you talk about opportunities to supplement hydronic systems and why a facility might go that route?

Certainly, there are opportunities to integrate electrification. One of the greatest advantages of hydronic systems lies in their design flexibility. Whether it's primary, primary-secondary or primary-tertiary configurations, efficiently transferring thermal energy across various zones is adaptable. Additionally, hydronic systems can be designed to align with the expected energy or thermal load that you expect to manage – the sweet spot, if you will – but during peak periods, the system can be supplemented with electricity. 

For example, if you’re running hot water baseboards, you can integrate some electric baseboards. Similarly for radiant systems, the option to integrate electrical components provides an avenue for fine-tuning performance during peak periods. If there is a system utilizing thermal storage or another renewable resource and we’re concerned about the availability of that energy source, we can design the system to trim out with an electrical radiant system. 

Emissions peaked in the U.S. in 2004. How much of an emissions reduction can we expect when they switch to a newer system? 

10 to 15 years ago, we really started to push innovation with the Department of Energy by using premium efficient motors, redesigning hydronics for greater efficiency and adding variable speed controls so that variable speed drives could be used instead of valves to change the flow. Over the years, we have revisited numerous buildings, retrofitting them with these advancements and seeing remarkable reductions of up to 30 to 40% in annual kilo-watt hours needed for heating and cooling operations due to the switch to variable speed technology. We’ve proven the resilience and effectiveness of this technology with retrofits that significantly enhance energy efficiency.

What workforce and education challenges do hydronics face?

For engineers and contractors who play a vital role in driving the future of building systems, there's been a lot of turnover in recent years. Many of the individuals who lived and breathed hydronics with that deep understanding are now retiring. As a result, there is a critical need for education, information and awareness to make sure that these technologies become integrated into the industry. That’s why Bell & Gossett launched the Building Better campaign, featured on Bellgossett.com, to get the word out about the benefits of hydronics and guidance on how to incorporate these designs effectively. Even for the homeowner, radiant floor heating – once considered a luxury – is now more economically accessible because of today’s technology.