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Your local inspector may have opinions about this, but you can buy all the components of an excellent LED system from your favorite electronics distributor, e.g. DigiKey.

Don’t waste your time or eyeballs with “driverless” devices. Get a chip-on-board LED, e.g. Bridgelux’s products, along with a matching driver (I like Luminus Devices’ small drivers - they have good startup and dimming behavior).

Aside from usual electrical safety, anyone designing what is effectively a luminaire needs to make sure that the driver matches the LED and that the driver is compatible with the dimmer in use. Matching the LED means that the driver produces an amount of current that that LED’s datasheet data is acceptable and that produces the amount of light that is desired and dissipates an amount of heat that can be managed. And that the LED’s voltage drop at the design current is in range for the driver. These LEDs are constant current devices, so you’re thinking about current first and voltage second. Read the datasheets!

Unfortunately many cheap luminaires are based on modules that are either driverless LEDs (which are terrible due to essentially unavoidable flicker and lack of regulation) or are line-voltage-supplied integrated devices. These are likely to be hard-to-find modules. There may not be room for a discrete driver and separate LED.

Yeah. It's not just cost, it's time. If I have to replace the fan, that's a trip to a hardware store, then a half hour (at least) to remove the old and install the new and get it wired correctly, so that it works and doesn't burn my house down. Then I have to take the old one apart far enough to fit it into the garbage can.

Replacing a bulb is a trip to my stash of bulbs in the laundry room, then throwing the old one in the trash.

I don't have time in my life for a fan with non-replaceable bulbs.

I mostly think the problem with these things is not the replaceability of the LEDs but the hideousness of the fixtures. This (and the fact that the fans will obviously perform very poorly) is the reason not to get the fans pictured in the article.

LEDs mean that the light itself is cheap so you can basically ignore energy usage concerns.

Generally, I think it is better to have:

- multiple dimmer sources of light instead of a single bright central light

- shades to diffuse the light (or lights pointed at walls or ceilings) instead of having bright point sources

- some ability to adjust brightness (eg reasonable quality dimmable LEDs)

- replaceable ordinary-looking bulbs from a reputable source (if you have 10 bulbs, it will be sad if one fails and you can’t get a similar looking bulb with a matching brightness and temperature)

- lamps, potentially wired up to light-switches for the room, which can provide light closer to where people will be and from better directions (eg maybe you sit somewhere where you can’t or don’t have a nearby wall-mounted light so a lamp can provide good light for reading). This also works in rented accommodation where one has less control over built-in fixtures.

- general considerations as to the purpose of the room (eg brighter cooler directable ceiling-mounted spotlights are more useful in a kitchen than a drawing room)

- sparing use of can lights (though this can be difficult if ceilings are low)

LEDs rarely die unless cooling is inadequate. DC/DC and AC/DC circuitry is a far more likely culprit.

In either case, learn to do hot air rework?

> 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 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

> 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 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.

I installed new fans a few years back. They all use those little 6" disc LEDs. They're replaceable. Is there some other type I've not heard of?

Have you tried replacing the LEDs or have you just assumed it's impossible because it's not a bulb?

It depends on the specific fixture.

But then, the problem is, it depends on the specific fixture. They aren't exactly putting "EASY TO REPLACE LEDS" on the box. I can't climb up to the store display model and start hacking away at it to see if I can get to the LEDs, replace them, and reassemble it correctly.

What I saw last time I was in a store where the fixtures were on eye level looked like a lot of glue, one-way tabs, and LED strips of unknown and custom provenance were being used. I'm not really looking for this sort of experience in a lighting fixture. YMMV and more power to you.

I know how to solder tiny parts and big parts, and I'm actually pretty good at it. I can generally take complex things apart non-destructively and reassemble them without damage. I can use a meter. I understand how electronic components work, and I even find pleasure in using them. I can safely troubleshoot and repair or replace a power supply.

Fixing an LED fixture is within my wheelhouse. I can repair them.

I just don't want to.

It seems like a much better use of my time and money to just screw in a different light bulb and forget about it.