Here is what we covered:
1- new case studies
2- onshore wind
3- combined PV/thermal solar
4- articles on climate change
5- DCC supply chain strategy
6- 2024 grid carbon intensity
7- electric construction equipment
Hope you can make the more friendly setting of our next meeting, bring your topics of interest as there will be no set agenda.
1- We’ve added 3 case studies to our list, if you’d like to contribute here are the guidelines.
- Using ‘My Electricity’ for a community building (section 3.1)
- Improving my Heat Pump (section 4.2)
- Hydro power, really! (section 7.4)
2- The government has an ambitious plan to double onshore wind generation from ~14 to 28 GW in the next 5 years. They have set up a Taskforce to drive this programme forward. One major obstacle is connecting this new capacity to the grid as NESO has just announced they have temporarily suspended new connection applications while they deal with the huge backlog.
Regen has published a briefing paper on the misinformation about wind power here. For a straightforward guide to countering such misinformation, see their myth-busting guide written for the All-Party Parliamentary Group on Renewable & Sustainable Energy.
3- Combined PV/Th solar panels are not new, but have not been popular for a variety of reasons. In a domestic setting, where residents would typically want the full PV generation potential, the excess thermal generation would need to be curtailed during many months of the year. A simpler/cheaper option is a PV panel with diverter to the immersion element in the hot-water tank.
A commercially application where large quantities of hot-water are needed, may be a suitable application for these combined solar panels. This example in London has some undefined claims such as “Most of the remaining 80% of the sun’s energy is converted to heat”. It is true that thermal systems can be more efficient in extracting the sun’s energy, but storing this can be problematic if not put to good use within a day or so. The cost of such systems can also be prohibitive depending on the application. These systems are only suitable for hot water during the summer months.
4- Over the past few months we’ve considered good and bad news articles about climate change. The datacentres in Ireland was one example, here are a couple more that were sent in:
Biomass boiler emissions are back in the news with this article from the Guardian. We covered the topic two years ago when it first broke. The referenced report only covered pre-2000 biomass boilers and wood burners.
While there are serious problems with many wood burners and how people use these, it is not correct to suggest that modern biomass boilers are ‘damaging’. Specifically, excluding production emissions which can be high in some circumstances, burning properly seasoned wood is carbon neutral. Equally, burning inappropriate wood containing glues/paints/preservatives is very dangerous under any circumstances.
The RHI scheme regulates emissions and requires participants to use certified biomass products. This includes:
PM2.5 regulated emissions must be less than 30mg/MJ, much less than the over 50mg/MJ for oil boilers, the target replacement technology for off-gas-grid buildings where heat pumps are less appropriate.
- Emissions are verified annually through boiler testing (independent MOT) and wood fuel sample testing in a lab.
- Many, maybe half, of boilers achieve below 20 mg/MJ
- Larger scale boilers (e.g. district heating) or smaller ones in populated areas, reduce this even further through appropriate filtration.
Here is another article to debunk Direct Air Capture as a potential solution. Interesting to see they the example publication they reference.
5- It’s good to see DCC has a Low Carbon Supply Chain Strategy, could this be an example for our district council to follow?
6- The Carbon Intensity of the electricity grid (CI) changes year on year. It is measure in Kg CO2e/kWh consumed. It applies regardless of who you buy your electricity from or what claims are made about how ‘green’ this is or what time you use it, see our Greenwash guide. A BBC UK electricity grid CI for 2024 article (go to 7th Jan report) suggests this has droped significantly to 0.124 Kg CO2/kWh. On the face of it, even below the 0.150 Kg CO2e/kWh used by current building regulations to assess ghg emissions from buildings.
A closer look at the text reveals this is for “generated electricity”, so ignoring losses which account for ~10%. A further ~20% needs to be added to convert CO2 to CO2e. Then there are the ~25% additional scope-3 emissions generated outside UK boarders. The resulting 0.205 kg CO2e/kWh is still an impressive drop from the 0.275 kg CO2e/kWh actual CI last reported by government in 2022. These are provisional numbers, you’ll see the actual ones reflected in ACT’s CFT when they are released.
7- Electric construction equipment has come a long way since we looked at these several years ago. At the time we did not think that battery technology would be sufficiently practical or cost effective. Clearly other criteria like noise play an important part.
Written by Fuad
Energy group coordinator