# LED light bulbs: power limit vs. form **URL:** \ **Category:** Factual Questions\ **Created:** [January 15, 2012, 9:29pm UTC](https://boards.straightdope.com/t/led-light-bulbs-power-limit-vs-form/609634 "2012-01-15T21:29:10Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [January 15, 2012, 9:29pm UTC](https://boards.straightdope.com/t/led-light-bulbs-power-limit-vs-form/609634/1 "2012-01-15T21:29:10Z")
Bought some LED light bulbs from Home Depot today. [PAR38 bulbs](http://en.wikipedia.org/wiki/Par38) are available with a brightness equivalent to a 125-watt incandescent bulb, but the [A19 bulbs](http://en.wikipedia.org/wiki/Edison_screw) are only available up to 60-watt equivalence. It’s not just Home Depot, either. I checked Amazon, and couldn’t find any brighter A19’s there either. Anyone have any insight into that difference in maximum available brightness? ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [January 15, 2012, 9:44pm UTC](https://boards.straightdope.com/t/led-light-bulbs-power-limit-vs-form/609634/2 "2012-01-15T21:44:18Z")
The problem is getting rid of the heat. Even though LEDs are \>5x more efficient than incandesents, they still generate heat, and unlike regular light bulbs, they aren’t happy operating at hundreds of degrees. This problem is compounded by the fact that they are designed to replace incandescent lamps, which never had very much though paid to heat dissipation. So, most LED “bulbs” have a large heatsink, and this limits how bright they can be for a given size. As technology improves, I expect to see LED replacements that are 200W+ equivalent. ---
**Author:** ![Nametag](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/nametag/32/406_2.png) [@Nametag](https://boards.straightdope.com/u/Nametag)\ **Post date:** [January 16, 2012, 1:38am UTC](https://boards.straightdope.com/t/led-light-bulbs-power-limit-vs-form/609634/3 "2012-01-16T01:38:37Z")
> **[World’s first 100 watt equivalent LED replacement bulb](https://newatlas.com/worlds-first-100-watt-equivalent-led-replacement-bulb/18659/)** > > Currently the brightest options for those looking to ditch their incandescent light bulbs in favor of the longer life and more energy efficient LED variety are those equivalent to 60 watt incandescent bulbs, such as the GeoBulb II. Things got a... ---
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [January 16, 2012, 2:26am UTC](https://boards.straightdope.com/t/led-light-bulbs-power-limit-vs-form/609634/4 "2012-01-16T02:26:03Z")
> [@Machine\_Elf](#): > > Bought some LED light bulbs from Home Depot today. [PAR38 bulbs](http://en.wikipedia.org/wiki/Par38) are available with a brightness equivalent to a 125-watt incandescent bulb, but the [A19 bulbs](http://en.wikipedia.org/wiki/Edison_screw) are only available up to 60-watt equivalence. > > It’s not just Home Depot, either. I checked Amazon, and couldn’t find any brighter A19’s there either. > > Anyone have any insight into that difference in maximum available brightness? PAR cans are designed to throw light in a specific direction; A19s are omni-directional. ---
**Author:** ![Snowboarder\_Bo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/snowboarder_bo/32/229_2.png) [@Snowboarder\_Bo](https://boards.straightdope.com/u/Snowboarder_Bo)\ **Post date:** [January 16, 2012, 2:44am UTC](https://boards.straightdope.com/t/led-light-bulbs-power-limit-vs-form/609634/5 "2012-01-16T02:44:18Z")
> [@jz78817](#): > > PAR cans are designed to throw light in a specific direction; A19s are omni-directional. Yep. Parabolic Aluminized Reflector. That’s why they have different lenses, so we can choose a particular beam spread as needed. “A” lamps are just designed to house a filament, with the glass frosted so the burning filament doesn’t blind people who look at the bulb. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [January 16, 2012, 3:58am UTC](https://boards.straightdope.com/t/led-light-bulbs-power-limit-vs-form/609634/6 "2012-01-16T03:58:13Z")
Must it be A19? Home Depot has 75 W equivalent A21 LED bulbs; specifically, the [Philips Ambient LED](http://www.homedepot.com/h_d1/N-5yc1v/R-202920469/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053). They’re just a bit longer than the A19 bulbs–probably fine for most fixtures. The screw base is the same. They aren’t cheap, but they are good.