This guide is aimed at those heat pump monitoring systems installed as part of the BEIS Electrification of Heat Trial, where a Passiv Monitoring data logger was installed as part of the monitoring bundle. The guide will explain how to swap the Passiv monitoring over to the Open Energy Monitor package.
Here is the guide: Heat Pump Monitoring switch BEIS EoH to OEM.pdf (635.1 KB)
WARNING
The changes needed involve mains wiring. If you are not absolutely certain that you are competent to do this, you should enlist the help of a qualified tradesperson.
Reflecting on last weeks EcoHomeLab presentation from Colin Meek on heat pump performance recorded from Ofgem RHI data: EcoHome Lab: In-situ heat pump performance in the UK (tonight 6pm UK time), It would be really interesting to compare data from systems that have participated in any of these larger trials e.g EST, RHPP, EoH with more recent data being collected on the same systems e.g via your guide @HydroSam on repurposing the Passiv Monitoring kit for use with HeatpumpMonitor.org.
If anyone knows the headline performance figures that EoH collected for their system. Ideally SPF H2 and H4 that would be interesting. Any insight on how the performance has changed after interventions would also be interesting.
I didn’t get any details from the trial on my system, and haven’t managed to get the hi-res data (happy to try and get my hands on it, if you wanted to help me dive into it and it would be useful).
I did however take daily readings from the meter display as I was trying to convince OVO and the trial what a bad job they did with the heat pump install. I was partially successful in that the pump was installed, but they wouldn’t change the heat pump unfortunately. I wasn’t sure what SPF H2 and H4 referred to but have just googled. The electric and heat monitoring on the EoH trial monitored all components so think that makes it H4. I have calculated COP figures in a big spreadsheet.
Headline figures
Heating season only
2020/21 - 2.0 (system repaired in Feb 2021)
2021/22 - 2.89 (system re-fitted in Aug 2021)
2022/23 - 2.88
2023/24 - 3.26 (Trial ended Aug 2023, join OEM in Sept 2023 and started making changes)
Annual SCOP
2021 - 2.18
2022 - 2.78
2023 - 3.02 (alterations to system started in Sept 23)
2024 - 3.07 (obv. up to Sept only, so likely to improve as heating comes back on)
Thanks @HydroSam, that’s great progress on improving performance!
What was the repair in Feb 2021 and re-fit in Aug 2021?
Is the immersion heater / booster heater monitored by a separate meter, is it both a booster and an immersion? Did you add the heat of the immersion to the heat output as well as the electrical consumption in your calculations?
Unfortunately I think it’s as far as I can improve performance without changing the heat pump, as the pump is so oversized for the property (covered that in other threads last winter) but always open to ideas.
Feb 21 to Apr 21 - heat pump external location moved as exterior pipe run too long. External lagging “improved”. 3 port valve rewired. Changes to pipework around buffer tank/volumiser. Multiple visits and a couple of audits.
Aug 21 - new contractor. Lots of pipework replaced (22/28mm mixed primary to full 28mm primary), buffer replaced for backup heater. Thermostat replaced for Daikin controller. Lots of settings changed. Unfortunately wouldn’t accept/didn’t have funding for replacing the actual heat pump which I’d already shown was oversized.
Elec into immersion is measured. Heat from the immersion isn’t measured, I’m not sure how you do that. I did quickly turn off the legionella cycle so it’s barely been used. Backup heater would be included as it’s inline on the primary circuit but it’s never been used.
The immersion has only provided 103kWh through its dedicated electricity meter since it was installed late 2020, and its not been used since late 2021, so I’m not sure it’s worth considering in my case.