Adveco Heat Pumps For Hot Water – A Sustainable Balancing Act

March 2024

Incorporating heat pumps for hot water provision in commercial buildings can be more complicated than you realise. Adveco is here to advise on the current advantages and disadvantages of the technology to help decide if heat pumps are the best fit for your project…

With growing concerns over sustainability and energy efficiency, commercial buildings are increasingly looking for alternatives to traditional gas water heating. Air source heat pumps (ASHPs) have emerged as a promising option, offering potential benefits in terms of reduced carbon footprint, and improved reliability. However, like any technology, ASHPs come with limitations that need careful consideration before implementation in a commercial setting. Adveco considers the key advantages and limitations of ASHPs for hot water provision in commercial environments, aiming to provide a balanced perspective for informed decision-making.

Heat pumps for hot water generation, such as Adveco’s FPI-32 or L70, work by extracting heat from the ambient air, utilising electricity to power the process. Compared to conventional electric resistance heaters, ASHPs can achieve significantly higher Coefficient of Performance (COP) values, translating to 3-4 times more energy output for every unit of energy input. This energy efficiency enables the ASHP to deliver equivalent heating for less input, and, since the unit utilises a renewable energy source – ambient air – carbon reductions are either minimised, or there may be no direct emissions during operation at all. This makes ASHPs an attractive option for businesses aiming to reduce their carbon footprint and align with sustainability goals.

The efficiency of ASHPs will decline as ambient air temperatures drop. The UK has a relatively mild climate, even winter extremes are unlike to prevent operation as most ASHPs will operate as low as -25°C. The efficiency will fall though as the unit works harder to achieve the typically cited 30°C working flows required for domestic operation. In extreme cold then, supplemental heating sources would be needed to maintain desired hot water temperatures. This is true of commercial applications in typical operation as the need for higher temperature working flow is a major safety requirement. To raise temperatures to the necessary 55-60°C means working the ASHP much harder as overall efficiency drops off at higher temperatures. Working the ASHP harder consumes more electric energy, which in turn negatively impacts operating costs. Although more efficient than resistance heaters, ASHPs still rely on electricity to operate. Fluctuations in electricity prices or grid unreliability can affect operational costs and system performance. For those transitioning from gas-fired water heating to ASHP driven systems, failure to factor in the difference in cost between currently cheaper grid gas versus electricity (as much as 3.5 – 4 times the cost) can become a major operational issue.

For this reason, an ASHP is rarely the single response for commercial scenarios with very high hot water demand applications such as restaurants, hotels, schools, universities, care homes, hospitals or industrial facilities. Large and/or higher temperature ASHPs are available yet may still not be suitable for all commercial applications. Their cost may be prohibitive and, depending on the size and capacity, ASHPs might require dedicated space for installation, which could be a limitation in buildings with reduced space availability. As with any hot water application, actual usage data, especially peak demand, is critical for accurate sizing and a good way to gauge if an ASHP is the correct response for the building in question. In most cases hybrid systems combining ASHPs with preferably electric boilers, such as the ADVECO FUSION systems, but also gas, as well as solar thermal as a source of mid-heating is going to be the preferred way forward. ASHPs are available in a wide range of sizes and configurations, allowing for flexible implementation in buildings of various sizes and hot water demands. Using the hybrid model, the ASHP is deployed to maximise the seasonal COP (SCOP) operating consistently at the greatest efficiency year-round to raise the water temperature to between 40-45°C. This is then passed into the system for topping up to the required 60°C minimum system temperature, by either the boiler or solar thermal and boiler combination. The ability to manage consistency of flow temperature, even when ambient temperatures drop, without driving the heat pump too hard is truly advantageous. Combined with a grid-connected boiler, such as Adveco’s ARDENT, delivers a robust all-electric, lower-carbon applications that will meet and exceed most current building regulations. Increasing the number of ASHPs is also a relatively simple option, so long as the building has enough connected amperage to support installation, meaning adjusting capacity needs as circumstances change is still relatively straightforward.

The initial purchase and installation cost of heat pumps for hot water can be higher compared to conventional systems. This can be a barrier for businesses with limited upfront capital, so it is worth investigating financial incentives on offer from the government to encourage the adoption of renewable energy technologies. In the UK small businesses currently have access to the same funding support and consumers seeking to replace existing gas boilers with an ASHP. However, for the time being, most commercial organisations will need to factor in the additional costs associated with purchasing units. Commercial-scale water heating is inherently more complex and therefore more costly to initially invest it, but ASHPs are relatively quick and simple to install. Once in place, when compared to gas boilers or other fossil fuel-based systems, ASHPs have fewer moving parts and require less frequent maintenance. A system based around an ASHP will therefore expect to demonstrate lower service costs and increased uptime for hot water delivery.

While ASHPs offer numerous advantages in terms of energy efficiency, environmental impact, and potentially long-term cost savings, their limitations need to be carefully assessed. Conducting a thorough feasibility study, considering specific operational parameters and available government incentives, is crucial before making a decision. By balancing the advantages and limitations of ASHPs against the specific needs of your commercial facility, you can determine if this technology represents the most sustainable and cost-effective solution for your hot water requirements.

Choosing the correct hot water heating application for a commercial environment requires careful consideration of various factors, including building type, hot water demand, climate, budget, and sustainability goals. Proper design, installation, and maintenance are crucial when optimising ASHP performance and maximising its benefits. Adveco, with more than 50 years of hot water design expertise, is here to help with consultation and can advise if ASHP technology or a hybrid mix of renewable technologies is the best resolution for your building project. Adveco’s temporary metering service and system sizing can also help create a more accurate financial analysis for the lifecycle costs of ASHPs compared to any existing and other alternative technology, including upfront costs, operating expenses, and maintenance requirements. This can provide valuable insights for decision-making whilst organisations wait for further potential government incentives to come into force.

By carefully considering all factors and conducting a thorough assessment, businesses can leverage the advantages of heat pumps for hot water needs while mitigating potential limitations, contributing to a more sustainable and cost-effective future.

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