Isaac Occhipinti, Head of External Affairs at the Hot Water Association, explains the role that hot water storage can play in the newbuild homes of the future.

There are many more UK homes now than 40 years ago: nearly 27 million today, compared to nearly 19 million in 1970. This inevitably puts upward pressure on carbon emissions.

Thankfully, significant changes in heating systems, comfort expectations, insulation, and use of appliances have transformed heat loss and emissions from housing, resulting in an overall downward trend in emissions.

In 2018 the government announced a commitment to halve the current emissions and energy consumption of newbuild homes by 2030 which indicates that we are certainly heading towards net-zero carbon. Furthermore, the Chancellor’s spring statement set a date of 2025 for all newbuild homes to be built with low carbon or renewable heating systems installed from this date. 

The direction of travel is clear, we need to futureproof the UK’s housing stock and, as an industry, we all must get on board with this, for both existing and newbuild homes. There is no justification for building homes which will have a legacy of high energy bills. 

We already have some of the most energy inefficient homes in Europe, and we need to break the vicious cycle of costly retrofit programmes. The Hot Water Association has always welcomed any commitment for new buildings to be futureproofed, enabling them to benefit from new technologies. One way of achieving this is to make them ‘hot water ready’.

If the UK is to increase its use of renewable technologies, then storage of some sort will be necessary. Currently, hot water storage is the only practical solution for turning the energy produced into something useful and storing it.

Be it a thermal store or hot water cylinder – whether for hot water only or in conjunction with space heating – putting a mix of useful energy into a hot water storage unit can reap benefits all year round.  

The National House Building Council guidance for hot water flow rates state that a single bathroom property with an en-suite shower should be looking for flow rates of 15l/min, and a property with two bathrooms would require 20l/min, making hot water storage systems a suitable choice for properties with two bathrooms or more. 

Some would argue that storage may be preferable in many single bathroom properties also, as there is the ability to heat the cylinder from renewable sources, solar thermal, and solar PV. 

Unfortunately, there is some evidence that one or two of the national housebuilders may be inappropriately specifying combination boiler systems, regardless of the number of bathrooms, as the SAP rating for hot water efficiency that some combis attract allow the housebuilder to reduce the amount of fabric insulation required to meet the Target Emission Rating. 

In some cases, it is reported that a high SAP rating combi can save the housebuilder anything up to £1,000 in labour and materials to meet the Target Emission Rate. Of course, a combi boiler would be able to cope with the demand of a large house with three or four bathrooms provided only one person was living there. 

Similarly, in a smaller house with one or two bathrooms, but with a high level of occupancy, all but the largest combi boiler might struggle to perform if three people all wanted to shower or bathe at the same time.

There has been some debate on the accuracy of SAP ratings, with some combi boilers in certain properties achieving the equivalent of one full dwelling emission rating point over other combis that have been designed to achieve more durability or reliability. However, that’s a talking point for another article.

The UK must deliver carbon reduction in domestic fuel use. The way we source, produce, and utilise energy must change to accommodate our commitment to net-zero.

Hot water storage solutions with ‘renewable ready’ connections compliment all sources of energy and offer homeowners comfort and convenience in both existing and newbuild homes.