Ultra high efficiency bicycle / office heaters

neptronix

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Made for lizards, but the ~150 watts coming out of the thing efficiently warms up a human MUCH better than a typical heat element + coil of the same power ( pictured on the left ):

image006.jpg

Example of such an emitter:
https://zoomed.com/repticare-infrared-heat-projector/

Apparently these things are efficient as hell because they transmit something more like heat from the sun than passive heat that just touches the skin.

Checking with a company to see if they run on DC and are therefore >= 72v operable, but i'd guess they are.
 
AFAICT they're just an incandescent bulb with a carbon-fiber filament, and appear to have a window/faceplate that is designed to specifically pass two IR bands (what they refer to as IRa and IRb). So it probably doesn't pass the rest of the energy it creates as visible light, and the trapped energy inside the housing would reradiate as one form of IR or another from the (probably ceramic) housing.

No experience with them, so I don't know how well a carbon-fiber filament handles vibration and shock loads, as it would get in a transportation device. (even some tungsten filament stuff doesn't work that well under those conditions).
 
OK, i created a 74 degree comfort spot in my 69f office with a 150w lizard heater to my right and a 70w sunlight simulator to the left.

bikeheater.jpeg

bikeheater2.jpeg

The unit can project about 100f 2 feet away and the heat is very penetrating, like being in a sun ray. I can feel the heat about 4 feet away from the emitter. There is very little heat on the sides or back of the emitter.

The interesting thing: the motion of air ( blowing a fan at it ) doesn't affect the heat felt.

This is amazing efficiency, for 220w of total heat, it does outperform a 1000w heater in my office as far as heating me up goes!

I think that 1-3 150W units would be perfect for a bicycle and actually, enclosing the bicycle may not be necessary to receive the heating. Running on a 72v battery makes it possible to get ~100w out of each 150w unit.
 
Fascinating narrative about your office innovation, observations, and test data. Well done ? :flame:

Will someone write:
Why aren't we using these 'personal heaters' at almost ever desk and especially inside a multitude of heat sinking concrete block offices?
 
neptronix said:
Made for lizards, but the ~150 watts coming out of the thing efficiently warms up a human MUCH better than a typical heat element + coil of the same power ( pictured on the left ):
If you use an insulated heating pad, very close to 100% of the energy of the pad gets into your body.

If you use one of these, you get perhaps 5% of the energy. The rest is radiated/convected as waste heat.

However, if it feels better - nothing wrong with that.
 
Having a history with trying numerous things like this I'll try and summarize my findings.

Seat heaters are great but you need to be able to control their heat precisely with a buck converter or fast PWM controller (fast enough so you can't hear it whine). If it's set just a little too hot it becomes uncomfortable but set just right you don't even notice it until you turn it off and you're like "why is it so cold in here". Also buying a cheap 12V car version will last awhile but they all break, best to just buy a roll of high strand count silicone or teflon wire and just stick a whole bunch to a seat cover and it will last forever, loooong lengths of bigger wire last way way longer.

Heated mice are great, I've always just shoved some power resistors inside my mouse because all the ones you buy are crappy mice but if you don't need a gaming mouse with lots of buttons probably fine.

Heat lamps like the ones you talk about are pretty good, about 200w one above your monitor will buy you a few degrees of ambient room temp reduction and as a bonus the IR radiation just makes you feel warm, like sitting in front of a fire.

Heat pad under your feet also works great.

Heated vest, not worth the plugging and unplugging but maybe with magnetic connectors? (I made one and then just turned it into a seat heater later)

Seat heater for the efficiency, heat lamp for the bonus psychological warmth, mouse if you have cold hands.

All of those combined with very warm clothes you can be comfortable while at a computer at surprisingly low temperatures for not moving. Is it worth saving money on heating? Eh, I still have the seat heater and mouse use them sometimes but wood pellets and mini-splits are so cheap for heating those are the wins in my book.

Bonus workspace tip: Get like 6-8x 90W+ 90CRI 5000K LED bulbs (yes this is a serious amount of indoor lighting) and set them up on a timer to flood your office (aimed at the ceiling for instance) with light during daylight hours. Monkey brain evolved to live in sunlight levels of light during the day, gets all confused otherwise. Also this is nowhere near sunlight lux but it seems to be enough to get the job done without consuming too much energy.
 
Stealth_Chopper said:
Fascinating narrative about your office innovation, observations, and test data. Well done ? :flame:

Will someone write:
Why aren't we using these 'personal heaters' at almost ever desk and especially inside a multitude of heat sinking concrete block offices?

That's exactly what i was thinking.

Yesterday the right side of me was sweating because the emitter was a little too close.
I had no idea 150 watts could be this powerful.

Redesign this emitter into sort of a large human sized dish and point it in the appropriate direction / distance from a human for comfort. The temperature 'control' can literally be a sliding bracket @ a 90% efficiency advantage over regular heating.

The only problem is that the heat is directional, so it's probably never a 'whole environment' heater but it is a FANTASTIC spot heater.
 
JackFlorey said:
neptronix said:
Made for lizards, but the ~150 watts coming out of the thing efficiently warms up a human MUCH better than a typical heat element + coil of the same power ( pictured on the left ):
If you use an insulated heating pad, very close to 100% of the energy of the pad gets into your body.

If you use one of these, you get perhaps 5% of the energy. The rest is radiated/convected as waste heat.

However, if it feels better - nothing wrong with that.

True, but an insulated heating pad and an office chair with various plastics and synthetic materials that's are not rated for the kind of spot heat that a heating pad may generate. Or at least, i am not interested in sacrificing a nice $300 chair to find out.

'on the body' heat works great, ie with a heated jacket powered by lithium. But probably not very stylish for the office. :)
 
scianic, thanks for your excellent reply. :)

scianiac said:
Bonus workspace tip: Get like 6-8x 90W+ 90CRI 5000K LED bulbs (yes this is a serious amount of indoor lighting) and set them up on a timer to flood your office (aimed at the ceiling for instance) with light during daylight hours. Monkey brain evolved to live in sunlight levels of light during the day, gets all confused otherwise. Also this is nowhere near sunlight lux but it seems to be enough to get the job done without consuming too much energy.

I tried that and it didn't work. Even the best ( CREE, etc ) do not emit the UV spectrum. That is the problem. UV generates the vitamin D response. Visible light does minor things, UV is the heavy hitter.

If you want to dive into the rabbit hole of why i have been basking under a metal halide light during winter for over a year, watch my video:

[youtube]Ihq2l8KYGgA[/youtube]

Also, UV LEDs exist but currently suck. I own the best product in that market and it doesn't work. metal halide and ceramic metal halide are where it's at. Everything that likes the sun flourishes under the influence of those lights because they're the most accurate representation of the sun currently available to us.


What i could really use is a heated keyboard. I'm a >=100wpm typist normally and type for a living but in the cold, i'm down to half or less that speed. Putting any kind of layer between the fingers and the keyboard would be a non-starter.
 
neptronix said:
True, but an insulated heating pad and an office chair with various plastics and synthetic materials that's are not rated for the kind of spot heat that a heating pad may generate. Or at least, i am not interested in sacrificing a nice $300 chair to find out.
If it's insulated, the heat doesn't get out the "back" of the thing. (And if any part of the pad touching your body gets hot enough to melt plastic, you will notice FAR before anything melts.)

https://www.amazon.com/Electric-Arthritis-Stiffness-Abdominal-Menstrual/dp/B07L5F17YL
https://www.amazon.com/Infrared-heating-rechargeable-cordless-Washable/dp/B0792KVSDM
 
Cool, but i couldn't stand the wearing it for 12 hrs part.

Hey, i went from 1200w of total office heating requirements to ~220w, and that's actually a bit too much power itself :mrgreen:
 
neptronix said:
What i could really use is a heated keyboard. I'm a >=100wpm typist normally and type for a living but in the cold, i'm down to half or less that speed. Putting any kind of layer between the fingers and the keyboard would be a non-starter.
A tale of hair, air, and warm:

Long ago in a poorly heated house with no insulation (so general heating was an expensive fail) I took my keyboard apart to clean the dog hair out of it, and found that the top half didn't fully close down on the area around the keys (allowing dog hair to migrate inside the entire body, not just under the keys), and I realized that this also meant that air could flow from the body of the keyboard to under/between the keys, if it was forced under there, and possibly keep the dog hair from falling into it in the amounts it usually did (at the time I had Lady, a wolf-pyrenees-samoyed mix).

So I took a slot-mounted large (palm-of-a-large-hand-sized) squirrel cage fan (intended to cool 1990s video cards) and cut the end of the keyboard open, and secured the fan's output "box" to that, and ran the fan first from just 5v, so it would be quiet. This wasnt' enough air, so I tried 12v (what it was meant to run on) and it didn't really do what I wanted...but I realized that since it blew air thru and out under my fingers, I *could* put a heater on the air intake and warm up my fingers without having to bury them in the dog's fur every few minutes to unfreeze them.

So I did that, first with a handy coffee-tea-mug warmer element right over the fan intake, which was insufficient, and then with a small heating pad's elements in a cylinder leading into the intake on the side (now top) of the fan. This worked fine, though I usually had to have the pad on high. I was also able to change the fan to 7v (wired between the 5v and 12v positive lines, and no ground connection) and it ran fast enough to warm my fingers without making nearly as much noise as at 12v.

Worked great for as long as I needed it in winters at that house. :)

KEyboards are made differently inside, so yours might not allow the same airflow path, and this technique might not work for yours.

But you could still make a little "hood" that sits "behind" the keyboard and above it a bit, that takes the heated air and pushes it over the top of the keyboard. (this is what I would have done if the other trick hadn't worked ).


This solution is probably too noisy if you need silence, but you could put the fan itself somewhere else, and duct the air from it to the end (or better, the back/top) of the keyboard, with the heating element(s) inside the duct.
 
"Redesign this emitter into sort of a large human sized dish and point it in the appropriate direction / distance from a human for comfort. The temperature 'control' can literally be a sliding bracket @ a 90% efficiency advantage over regular heating."

This oscillating parabolic resistance (400-800W) room heater might be modified to the 150W source that you lIke.
The motor draws current but ( on/off. )
 

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