There has been a delay to the anticipated HNTAS consultation release which was expected in Q4 2024, but according to DESNZ is now imminent in Q1 2025. This has caused significant uncertainty in the industry, but although we are awaiting the concrete details, one thing is certain: HNTAS will bring big changes. It will impact the way the industry delivers new heat networks and operates existing ones, with a new emphasis on demonstrating minimum levels of energy performance using measured data. This means new requirements for metering and monitoring systems. With the delay however, there are mounting risks for those building new networks or retrofitting existing ones.

The market is crying out for this consultation because, for many organisations, it’s the first time they’ll see detail around how HNTAS will work. In addition, while the expected release date for the consultation has repeatedly moved back, the date that HNTAS will come into force (January 2026) has not moved. Design teams, contractors and operators are making decisions today that will influence whether or not the resulting heat networks will be compliant with HNTAS. So, the burning questions are: how do you manage this risk, how do you anticipate the regulation, and how can you mitigate the risk of non-compliance?

In our view, there are many things that you can be doing now to get ahead of the game and be prepared for HNTAS: 

  • Ensure that your design includes bulk heat meters for heat generation in the energy centre and at the boundaries of blocks.  This is essential for providing the data needed to calculate KPIs like heat loss and bypass flows.  If the system includes substations (e.g. dividing district and communal networks) then you should install bulk meters on both sides of the plate heat exchanger.
  • Implement sub-metering for your pumps in the energy centre to measure the energy used by the pumps (another expected KPI under HNTAS) and to enable monitoring of the efficiency of the system. 
  • Install a flow meter to measure top-up water going into the heat network. This will help determine if there are leaks and whether large amounts of untreated water is being added to the network.
  • Ensure that you have a way of measuring energy input to the central heat generation plant; whether that be gas (to boilers) or electricity (to heat pumps). Accurate measurements of energy into this system will be a key element of the HNTAS regulation, and therefore it is essential that this is measured correctly.

These are a few of the steps that we believe are going to be essential in preparing for HNTAS as the clock runs down.  We say this, because the key principals of HNTAS have not changed – it is there for performance analysis, energy efficiency and regulatory reporting. 

In addition, all of these meters and other measuring devices should have a secure, reliable means of being remotely read. It is likely that bulk meters will need to provide data on 5-minute intervals, while dwelling meters will have to provide data at 30-minute intervals.

The importance of data security cannot be overstated and therefore we believe that HNTAS will almost certainly include a requirement for systems to be compliant with GDPR. Here is what that may look like in practice:

  • Data transmitted from meters will have to be encrypted to protect confidentiality, integrity and availability. Unencrypted systems don’t meet the basic requirements of GDPR and so are unlikely to be permitted. Remember that meter data from dwellings is classed as personal data, even if it uses unique identifiers rather than names or addresses. 
  • Unencrypted systems are not secure and do not comply with GDPR. Sitewide wired M-Bus falls into this category and the use of this, which has previously been a standard for transmitting metering data, are unlikely to be permitted under the new regulations.

Finally, a word about HIUs. HNTAS is expected to mandate that HIUs must pass the latest BESA test in order to be compliant; this is now a pass / fail test. If you are designing in an HIU that has not passed the test you could end up with a non-compliant system.

In conclusion, we know that the delayed release of the HNTAS consultation is creating significant challenges for the heat networks industry. Due to the January 2026 deadline remaining fixed, decisions today must anticipate the regulations whilst awaiting precise information.  To mitigate the risk of ending up with a non-compliant system, it is crucial to understand the likely outcomes. 

Guru Systems can help you on the get ahead and simplify your journey to HNTAS compliance. Our advanced solutions are designed to meet the most stringent requirements for energy performance and data security. Our systems use an encrypted wireless mesh network that will remain compliant.  With secure data transmission and GDPR-compliant systems, you can trust that your heat networks will be ready for the new standards. 

Get in touch to find out how Guru Systems can help you stay ahead and ensure simple and seamless compliance with the evolving HNTAS regulations.