Comment by nekusar | Hacker News Reader

Comment by nekusar | Hacker News Reader

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> I'm old enough to remember when I was promised LEDs would last approximately forever without having to be replaced.

Yep, I remember that when Obama banned most incandescent lights because 'LED lighting is the future and 100 year lifespans blabla'.

Mind you, we used CFLs in the warm season, and incandescent in cold seasons. Incandescents are 100% efficient in cold seasons (heater AND light).

As much as I deign to admit, Trump reversed Obama's ban. And Biden reinstated it. I don't think Trump reversed Biden's reinstatement though. He's been way too busy with wrecking the country for shits and giggles.

But what the LED manufacturers figured out is they could overdrive LEDs and use substandard electronics for driving them. So sure, LEDs are more efficient, but they're the same old burnout cycle that's forced on us.

And we know all of this by the fact that Phillips makes "Dubai Lamps", and you can't buy them at any price. https://hackaday.com/2021/01/17/leds-from-dubai-the-royal-li...

I regret to inform you that Obama did not ban any light bulbs.

Those initiatives were legislated during the Bush administration in 2007.

They were rolled back some during Trump's first term, in 2019.

Restrictions were re-introduced under Biden, in 2022.

> Incandescents are 100% efficient in cold seasons (heater AND light).

That's resistive heating, which is the most inefficient means of heating. Worse than natural gas or heating oil, and much worse than a heat pump.

> Worse than natural gas or heating oil, and much worse than a heat pump.

Worse than a heat pump, yes, but very arguable whether NG is more efficient. Arguably, NG powering central electric power generation and then used for resistive would be overall more efficient. Central NG will be more efficient and also there’s substantially less opportunity for NG leakage if piping was reduced.

NG is definitely cheaper (at least in the US), but that’s not really related to efficiency or emissions cost.

It doesn't take into account leaks, but modern NG furnaces are substantially more efficient than modern gas power generation.

I’m not sure that’s easily quantifiable. Yes, thermal efficiency of modern NG furnaces can be ~95% or whatever… but you can also run multi stage heat capturing NG power plants that have very high overall efficiency too. Not 95, but at 60-70%, it’d be a potential wash in terms of emissions if leaks are ~10% (especially considering how much worse unburnt NG is as a leak vs when it’s burnt).

Also, if you’re in the electric ecosystem, swapping to heat pump systems will obviously be lower overall power in basically every scenario, and it gives an easy transition path unlike NG.

> Also, if you’re in the electric ecosystem, swapping to heat pump systems will obviously be lower overall power in basically every scenario, and it gives an easy transition path unlike NG.

Maybe... I've got a NG furnace now and am looking at adding a heat pump, and even with a pretty expansive budget, I'm struggling to make the numbers work on actually removing the furnace entirely vs. doing heat pump + furnace. (And the near-impossibility of upgrading my home service past 100A makes it extra complicated if I want to electrify everything.)

I’m not making the argument for total amortized cost. I’m just talking about per energy unit cost, specifically in terms of CO2 or emissions.

If the evaluation is total lifetime cost to you, using the equipment you currently have almost always wins out. Same with purchasing more efficient hvac and such: the cheapest/lowest efficiency hvac is almost always the most cost effective. That tide could turn with sharp increases in NG or electric prices… but it hasn’t historically been true for many years.

> Arguably, NG powering central electric power generation and then used for resistive would be overall more efficient.

It depends on the particular furnace or NG generator in question, but if you take the best case for each, then this does not appear to be true.

The most efficient combined cycle NG plant is around 65% efficient, without considering transmission losses. The most efficient NG furnace is 90+% efficient.

https://en.wikipedia.org/wiki/Gas-fired_power_plant

https://en.wikipedia.org/wiki/Forced-air_gas

What do you mean by "inefficient"? 100W goes into the bulb and the same 100W go out. Energy remains in the room. How is it different to burning gas to get the same 100W? Or am I missing something?

It's inefficient of money.

A 100 Watt light bulb consumes 100 Watts. It emits 100 Watts. That's 8,190 BTU every 24 hours, and it is perfectly efficient at doing this.

At $0.1745 per kiloWatt hour, it costs $0.419 to produce those 8,190 BTUs.

A natural gas furnace at 90% efficiency, meanwhile: Yeah, 10% goes right out the pipe and is lost.

But if natural gas costs $1.346 per therm, then producing 8,190 BTUs of useful heat costs closer to the realm of $0.123.

One thing costs about 42 cents. The other thing costs about 12 cents. 42 moneys is more than 12 moneys. :)

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I might opine that the most cost-efficient way of dealing with an incandescent light bulb is usually to immediately replace it with an LED bulb, and then landfill the old thing even though it still works.

4-packs of 100 Watt-equivalent LED bulbs are $12.97 at Wal-Mart, or about $3.24 per bulb. If it's the heating season and natural gas is being used at 90% efficiency, then replacing the incandescent pays for itself in about 300 hours of use. The LED will then continue to work and save money for thousands of additional hours.

For the most efficient kinds of natural gas power plant (combined cycle), around 35% of the energy (from burning NG) is wasted.

Compare that to a modern NG furnace, which can be 90% efficient or more.

So if you just want heat, burning the NG directly is generally more energy efficient than burning NG to boil water to drive turbines to generate electricity and then converting that electricity back to heat via resistive heating.

In addition to what the other commenters say about electricity generation, heat pumps are more than 100% efficient. So using an incandescent bulb as a resistive heater loses there too.

I don't care much on the politics of it all because I do think a lot of it is silly, especially with how profit-motivated companies will still find a way to profit.

I will say I've had a number of Hue bulbs starting back in about 2018 and have yet to lose one except for a surge that got an unprotected strip. Otherwise, plenty of white and color bulbs have worked steadfast for nearly a decade while costing a fraction in energy. That said, I do miss the warmth of incandescent lighting, but I don't miss replacing bulbs multiple times a year

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