You’re right a lot of this will be domestic lighting changing.

That said, UK manufacturing decline also correlates with this as that’s very energy intensive. Also don’t rule out fridges, old 90s fridges were very energy intensive compared to today.

> Improved efficiency is also supporting reduced use in the industrial sector – as has a general decline in GB industry and associated intensive electricity use

https://energy.drax.com/intelligence/2024-the-year-electrici...

> This is part of a larger trend. Demand has been falling by 5 TWh per year since 2005. Improving efficiency (lighting, televisions, fridges, etc.), fewer homes using electric heating, and deindustrialisation all play a part

https://reports.electricinsights.co.uk/?p=2065

Street Lighting. Sodium lamps used 250-500W and LEDs are 50-150W. Councils have been replacing the former with the latter ever since it was possible, as the savings were apparent after only a few years (and, the early investors could sell the old bulbs to authorities who did not have the funds to invest)

Notably low pressure sodium is more lumens per watt than a typical LED.

The main energy saver is simply that the newer LED lights are dimmer!

You’re leaving out the part where the sodium lights wasted a lot of their lumens by tossing them into the sky. LEDs can be dimmer because they can be directionally controlled.

That's trivially solved with a reflective housing, which nearly all sodium lamps I've ever seen had.

While it is definitely true that original power drops were due to lower lumens, few things:

- reflective housing is super inefficient (~70% losses on the bounced light off typical material, at the top end expensive stuff still ~23%), still better than just losing the light upwards but not as many lumens on the road as a lab test would show

- Today LEDs are more efficient than sodium

Some math: 100W HPS cobra head lamp prdouces 9.5k lumens, including ballast it draws ~133W from the wall. Lab test shows about 70% of the lamp's light leaves the fixture (with the rest being lost in the housing) leading to ~7k lumens exiting. Roughly 53 lm/W.

LED cobra head lamps get like ~125 lm/W on the low end + fade much more slowly than sodium

Don't low-pressure sodium lamps get like >2x efficiency gains over HPS?

They do.

People don't like them mostly because they're orange.

Astronomers definitely do like them because they're orange, and they can filter it out of their photos.

Why there weren't dimmer low pressure sodium lights?

There is also a substantial saving in household appliances from all the EU laws as well that have pretty substantially cut power consumption, including a lot of computers and devices at idle.

The UK household has quite significantly cut its power due to all these power saving innovations, far in excess of the actual drop because industry has increased its percentage of the mix over time.

There has been a decline heavy industry and the article says industrial consumption has declined a quarter since 2005. Deindustrialisation is the major driver.

Power management (ACPI) in desktop computers also arrived in the late 1990s. Power saving sleep modes have a big impact.

Computer fleets across a country do not upgrade immediately so the lag may contribute.

And ACPI was just one energy saving initiative of that era.

In the summer. In the winter the heat from the bulbs would help heating the homes, offices, stores, etc.

Or you could use all the saved energy to run a heat pump, which is even more efficient.

Heating the ceiling with the light is an extremely inefficient approach to heating a room.

Recently installed a bunch of incandescent bulbs because I had them at the bottom of a drawer.

I was surprised how the small amount of infrared from them makes rooms feel more pleasant to be in. It's a warmth on the skin, rather like having a fireplace going.

If I weren't paying the electricity bill, I would totally fit them everywhere.

100W of heat is like having another person in the room.

It's nothing at all like having a fireplace going - unless they're on fire, in which case both of you have a problem.

I suspect the bulb is better at radiating that heat to my skin though

This sensation of warmth while being in a nominally cold room can also be created with microwaves. A couple of such systems were designed when microwaves were the new hotness. Turns out it might cause cataracts, though.

the heat rises out of your baseboard just the same. If you’re heating your house resistive electric, you can just leave everything powered on all winter.