Thread by @shortthought

I'm seeing some express the view that retrofitting old homes may be a false economy as cheap renewable energy, with low/zero carbon heating/cooking solutions will mean it wont matter too much how much energy we use, as long as it's zero carbon.
Let's explore that.
1/14

First, the best energy strategy is lower use; however, as we are moving to an energy future where we stop using fossil fuels, technically, we could not worry about how much we use.
But we still need to, as it will still take some decades to achieve this global ambition.
2/14

Energy also isn't free & it looks unlikely that it'll be 'cheap', especially as it's taxable.
An off grid revolution will be in our future but currently, the costs are complex & limiting.
What isnt limiting is retrofit, as once done, every future occupant benefits.
3/14

Retrofitting can be expensive but it doesnt need to cost £80,000+ by being 'deep'. By reducing air exchange and insulating properly for a few hundred to a few thousand pounds, homes can require far less energy to heat.
Warmer homes, less heating need & better air quality.👍
4/14

Air quality is often ignored but by lowering air exchange, exposure to poor air quality is reduced. This can throw up an issue with ventilation if too airtight, which mechanical ventilation fixes but this is usually a deep retrofit concern.
Healthier homes for generations.👍
5/14

The generational impact is vital as apart from window replacement costs, retrofit payback is long term. This isn't the same for eg-heating, as like windows, they need replacing/upgrading.
Just like our energy system, esp as electricity reliance/demand is projected to rise.
6/14

A projected increase in elec demand won't necessarily mean cheaper energy. This is because the infrastructure to meet demand isn't just, eg-new turbines, but substations, cabling etc. Consumers & taxpayers will absorb that cost, plus component material prices are increasing.
7/14

Plus, electricity prices arent going down & any levy removal (currently at around 23%) on electricity will be placed elsewhere.
There is another tax factor and it's a decrease in oil/gas tax revenues, broadly due to the cost of decommissioning. This trend isnt ending.
8/14

At this point, it's fair to highlight that solutions such as heat pumps deliver up to 3 times as much heat energy to the system as they consume in electrical energy. This means they'll use less energy & any home refurb to accommodate them is a permanent investment.
9/14

There's another HP benefit & it's their need to be constantly on in certain months. This is good for a building, as it keeps a more constant temperature, ensuring in colder months homes are dryer, with less condensation.
They can even be rigged to cool homes in the summer!
10/14

However, HPs are not a silver bullet. Most homes don't need summer cooling/heating & heat pumps need a space impacting cylinder.
Plus, there are other solutions, eg-solar thermal (also needs cylinder), electric boilers or thermal batteries, eg-Sunamp (can replace cylinder).
11/14

Retrofitted homes with the correct technologies may use less energy than heat pumps; even with a lower COP. Plus, not made with fossil fuels, have lower maintenance costs & lifespan. Eg-Sunamp's 40yr expectation!

Reducing consumption has many benefits.
12/14

And we must understand this reality & that energy demand will increase.
The grid will handle our needs but it's responsible to not simply say, 'dont worry about energy consumption; we can generate more'.
This ignores future demand & how long it takes energy to get online!
13/14

Retrofitting is a key component of our energy & healthy & better home future.
Unlike energy, once completed, it's benefit is not subject to outside impacts, as energy is (eg-recent/projected price rises).

Any decarbonisation strategy must have retrofitting at its heart!
14/14

For anyone interested, there is an industry led National Retrofitting Strategy (NRS); which faces challenges to implement but sets out a broadly deliverable timeline and approach. #ClimateAction
constructionleadershipcouncil.co.uk/news/national-…