nZeb The Challenge Ahead


With nZEB now a well-known term, James Porter, Euro Gas Sales Director, looks at the challenge ahead.

With the introduction of the nearly Zero Energy Buildings standard (nZEB) for new public sector buildings at the end of last year, the industry has seen the rise of the nZEB compliance conversation. Looking ahead to December 2020 all new non-domestic buildings will have to conform and the question is how?

The standard requires buildings to use 60% less energy than the current regulations plus 20% of the primary heat source to be met by renewables. There are opportunities to reduce this 20% to 10% by increasing the efficiency of the building, but for the majority of cases the 20% threshold seems to be the driver.

Now, you could look at this and say what’s the problem? There are ample technologies available to help reach this target and, in most cases, exceed it, but it does pose a few commercial questions along the way.

Within the mechanical HVAC world, the challenge is always budget versus aspiration and whilst delivering a fully “green” building is very attractive for some of the blue-chip companies, other smaller companies struggle to juggle the legislation versus the social responsibility.

It is fair to say that for the average building owner or developer, if this is tackled in the wrong way their capital cost for M&E alone could be huge. Surely the answer is a slightly more rounded view which integrates tried and tested technology alongside the renewable alternative.

This is the approach we have focused on in Euro Gas. The technologies in question are not new to the market, most of them have been around for many years, but they have not always been present on your typical commercial HVAC project. The headache is not how to use them, but how to integrate them to an extent whereby nZEB can be achieved and in some cases exceeded. The options seem to boil down to two or three, once you take the practicalities into consideration:

The issue with the CHP option is determining the size required to comply with the model. Unless used to run your heat pumps, the electrical load can end up being huge for a building which does not need it. The complication with trying to integrate them with your heat pump can be that you end up with an extremely complex design which is all reliant on mixed technologies.

Heat pumps seem to be the one technology which has the flexibility to work on these schemes. If it’s a large commercial load then the electric air/water definitely fit this bill whether you are using them for heating, domestic hot water or a mixture of both. The key we have seen is in the integration. Designing your hydraulic system to be such that the heat pump becomes the master, and therefore the client sees the maximum return on investment, is definitely the way to approach this. Gas condensing boilers can easily work alongside these technologies when well designed to purely be there as either back-up or support. The same can apply to domestic hot water production. Using the system as a pre-heat makes infinite sense as you not only increase the efficiency of the system, but also add longevity as the plant does not have to work as hard as it was previously doing. Euro Gas has a design philosophy which will help at the early or detailed design stages. The same could be said for gas absorption heat pumps (GAHP). If the overall output of the building fits the profile then these can be a great alterative. Gas can be seen as a dirty word in the new world of HVAC but in reality, this technology can be one of the most user-friendly approaches. Utilising a small gas burner for the periods where the absorption cycle is less effective means that the overall efficiencies are high. The beauty being that this is not exclusive to areas of natural gas as it can also run on LPG.

Our challenge as a partner is not just in the design. It is probably fair to say that at times some of these schemes can be complicated. The “on paper” approach can only go so far, so it is important that we are there to support contractors to ensure that the designed system can work in the real world. The client, at this point, is looking forward to their new, compliant and greener building. It is most definitely our job to help and support all involved to ensure that this is the case.

Overall, Euro Gas firmly believes that the devil is definitely in the detail. We urge designers and engineers to engage with us at the earliest opportunity. Our principal manufacturers are diligently working to stay ahead of these curves and are expanding and engineering their way into a very different looking future. As a leading supplier, our job is to work with these manufacturers to ensure that when a project lands in front of us, we know what suggestions or concepts to propose.

2019/2020 will be extremely interesting times for our industry. For once this seems to be regulation without the need for a golden egg. The technology can stand on its own two feet and the clients can see a significant saving going forward. The key area to focus on is the integration and selecting the right product. 

Get in touch to get more information, or to discuss your specific requirements with one of our team.