Question 1

What is a low carbon technology assessment?

Accepted Answer

It is the assessment of low carbon technology devices, such as heat pumps, electric vehicle chargers and inverter connected generators including PV, wind and battery, for standards compliance and their connection to the public electricity distribution networks in the UK and Ireland. In practice this means checking a device against the engineering documents and product standards that govern its behaviour on the network: the ENA power quality documents EREC G5 and EREC P28, the generation documents EREC G98 and EREC G99, the international generator standards EN 50549-1 and EN 50549-10, and the EMC product standards in the BS EN 61000-3 series. Alongside document compliance, we model and assess the harmonic performance of devices and their voltage fluctuation performance, including flicker and step voltage change, and we consider the assumptions in EREC G5 against real harmonic data. If you would like to know more about our LCT work, email LCT@threepwoodconsulting.com.

Question 2

What is a G99 compliance assessment?

Accepted Answer

EREC G99 is the ENA engineering recommendation covering the connection of generation to the distribution network, with EREC G98 applying to smaller installations. We assess devices for compliance with G98 and G99, as well as the international generator standards EN 50549-1 and EN 50549-10. A compliance assessment reviews how a device performs against the technical requirements these documents set for connection to the public electricity distribution networks in the UK and Ireland, and it typically applies to inverter connected generation such as PV, wind and battery devices. Generation compliance rarely stands alone, so we often assess the same device against the power quality documents EREC G5 and EREC P28 and the EMC product standards in the BS EN 61000-3 series, and we can model harmonic and voltage fluctuation performance where measured evidence needs interpretation. This gives manufacturers and network operators a single, coherent view of a device's compliance position. Questions can be sent to LCT@threepwoodconsulting.com.

Question 3

Which power quality standards apply to LCT devices?

Accepted Answer

Key documents include ENA EREC G5 and EREC P28 for power quality, plus the EMC product standards BS EN IEC 61000-3-2, BS EN 61000-3-3, BS EN IEC 61000-3-11 and BS EN 61000-3-12. We model and assess the harmonic and voltage fluctuation performance of LCT devices against these requirements. Harmonic assessment considers the distortion a device introduces to the network, while voltage fluctuation assessment covers effects such as flicker and step voltage change. Both matter when heat pumps, electric vehicle chargers and inverter connected generators such as PV, wind and battery devices connect to the public electricity distribution networks in the UK and Ireland. Our work goes beyond simply applying the documents: we consider the assumptions in EREC G5 against real harmonic data, and through our Networks Discovery research we have tested whether the standard's harmonic aggregation assumptions remain correct. For advice on which requirements apply to a specific device, email LCT@threepwoodconsulting.com.

Question 4

What is the ESB Networks LCT Register?

Accepted Answer

ESB Networks began developing an LCT Register in October 2024 to record low carbon technology devices connecting to its network in Ireland. Threepwood is supporting the development of the register and acts as ESB Networks' agent for any LCT device requiring registration. Low carbon technology devices include heat pumps, electric vehicle chargers and inverter connected generators such as PV, wind and battery devices, the same categories of equipment we assess for standards compliance and connection to the public electricity distribution networks in the UK and Ireland. To help manufacturers and suppliers navigate the process, two documents are linked from our low carbon technology assessment page: the LCT Register Overview Guide, which explains what the register is and how it works, and a registration guide describing how to get devices registered. The register itself is published by ESB Networks. If you have questions about the register or whether your device needs to be on it, email LCT@threepwoodconsulting.com.

Question 5

How do I register an LCT device with ESB Networks?

Accepted Answer

Our LCT Register Overview Guide and registration guide, both linked from our low carbon technology assessment page, explain the process step by step. As ESB Networks' agent for LCT registration, we can help you through it: email LCT@threepwoodconsulting.com with any questions about registering your device. The register was begun by ESB Networks in October 2024 to record low carbon technology devices connecting to its network in Ireland, and it covers device types such as heat pumps, electric vehicle chargers and inverter connected generators including PV, wind and battery devices. The Overview Guide explains what the register is and how it works, while the registration guide walks through how to get a device listed; the register itself is published on the ESB Networks site and linked from our page. Because we also assess LCT devices for standards compliance across the UK and Ireland, we can advise on both registration and the wider compliance position of your device in one conversation.

Low Carbon Technology Assessment

Low Carbon Technology Compliance and Assessment

ESB Networks LCT Register

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