Monday, 22 February 2021

Renewable heat installation rates

A friend asked me if I think that heat pumps are still a 'niche' technology or are becoming mainstream. She was surprised by the number of companies able to install in this area - the MCS website finds ten within 30 miles of Cambridge. So I took a look at the statistics for take up of the renewable heat incentive for heat pumps (domestic). Here is a chart showing cumulative installations.


Domestic Renewable Heat Incentive cumulative applications by month, data from [1]. The steep rise up to April 2015 includes legacy applications.

Friday, 29 January 2021

Common mistakes in energy reporting that make me groan

A conversation on Twitter recently reminded me of how often poor reporting of energy gets units mixed up - or is misleading in other ways. Here are some examples of my personal pet peeves published online : confusing power and energy, reporting power but not energy for storage, and reporting capacity but not energy for generation. I have included examples from mainstream news, trade magazines and even the IEA. If I have quoted your publication, rest assured you are not alone in making these simple, but irritating (and sometimes confusing) errors.

Wednesday, 20 January 2021

How have we reduced our domestic energy use?

Domestic energy bills have reduced about 20% over the last decade - in terms of energy used. We have reduced consumption in lighting, refrigeration, TV and electronics. Unfortunately, prices have risen such that the overall bill has often increased – probably that is one of the reasons why we are using less, to save money. In this post I attempt to dig deeper into the mechanisms behind these changes and see what lessons can be learnt.

Friday, 8 January 2021

Energy Ratings for heat pumps - what do they mean?

Example energy label from [1]
Do you check the energy labels when you buy appliances such as washing machines or refrigerators? I hope you do. To make comparisons easy each product has  a rating, which is generally between A and G except for some appliances it goes up to A+++. This is helpful only if you know what the best or typical rating is. In any case, the rating does not actually tell you what the efficiency is or typical energy use would be - hence my advice has always been to look for these on the energy label. I would love to be able to say the same for heat pumps but there is nothing like that on the energy label for heating appliances. The rating is the best we have to go on. Here is a picture of the design of the energy label for a heat pump with integrated hot water cylinder, so it supplies hot water for the taps as well as for the central heating system. To understand what this means I have been reading the legislation behind it [2].

Friday, 18 December 2020

Climate change stories to be cheerful about

It has been a very difficult year for several reasons. But it was not all bad. To cheer us up over the holiday, here are my favourite good news stories from 2020 - including coal consumption down, renewables up, beavers for flood management, hope for the survival of coral, help in eating more plant proteins, and changes to our travel behaviour.

Friday, 27 November 2020

Options for water supply in Cambridge.

CambridgeshireLive news recently reported that plans for new homes in Cambridge could be stymied by lack of water supply. I have been reading the report behind these findings [1]. It is good to know that the water supply constraints are being taken seriously at last  – and that solutions are on the table too. Demand side measures include leakage reduction, rainwater harvesting in new developments, and prioritising public water supply over agricultural use. Measures to increase supply include land management schemes to improve water retention and possibly hooking up to a new reservoir in Lincolnshire.

Wednesday, 4 November 2020

Hair washing - survey results

Thanks to everyone who completed my survey on how we wash our hair in the shower. I am concerned about this because of my general concern about water use as well as energy because showers can use a lot of both. Your shower could account for half your water consumption or even more*. This is more of an issue for people with long hair, although you do not have to have long hair to take a long time in the shower. The results of the survey demonstrate a wide range of behaviour, even though I am sure there was a tendency for respondents to be more eco-conscious than average - otherwise why would they take the time to fill in my survey? Anyway, here are my main findings.