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Restoring the Old Way of Warming: Heating People, Not Places

lowtechmagazine.com

31–40 of 99 posts

Re: Restoring the Old Way of Warming: Heating People, Not Places

#31

3 Points: 1. Cars are moving into this with heated seats, and even heated steering wheels. Electric cars in cooler climates that don't have the excess heat production of an IC engine will depend on it to keep occupants warm. 2. There was an article a while back on HN about a fellow that had a computer desk with a heated keyboard, heated mouse, heated floor mat (designed for animal cages) and a warm incandescent light…

Number 3 is already here. Your electric blanket can be connected to an internet connected power strip which can be turned on an off with an IFTTT recipe. Your Nest thermostat and this can both be scripted to turn on based on yout smartphone location.

Re: Restoring the Old Way of Warming: Heating People, Not Places

#32

Earlier quoted context omitted.

Agreed. They seemed oddly insistent on pushing their implicit premise that heating large volumes of air is wasteful. http://krisdedecker.typepad.com/.a/6a00e0099229e8883301bb07e... However, the volume of air is not inextricably linked to energy expenditure, which only happens when heat flows down a gradient, not while it sits in a room. We can model it like a simple resistive circuit; the equations are analogous. V =…

Nobody is advocating a bad insulation. You said it yourself, P ~ ∆T: I think the rationale here is to lower ∆T and provide heat to your "spot" as needed. It's probably not going "mainstream" quickly either, but it can save you some energy: it's not so wild to imagine lowering your thermostat a few degrees and get a localized heat source if you seat in that one spot most time.

Right, as long as heating has a nonzero cost you will be able to forego it and save money. The more interesting question is whether or not you can maintain the same level of comfort (same interior temperature) in a small region of the room with a local heater and save money. Since exterior temperature and comfort temperature are fixed, this is the justification for ∆T=const. Most people decide that heating is worth the price as it stands; the real question is "can we make it cheaper via spot heating?"

Alricb and I think the answer is "no." Over the lifetime of a house, I would guess that the money you would spend on spot heater(s) and their electricity would net a better return if you invested it in insulation. After all, insulation keeps heat out during summer and air conditioning is much less efficient than heating :)

Re: Restoring the Old Way of Warming: Heating People, Not Places

#33

3 Points: 1. Cars are moving into this with heated seats, and even heated steering wheels. Electric cars in cooler climates that don't have the excess heat production of an IC engine will depend on it to keep occupants warm. 2. There was an article a while back on HN about a fellow that had a computer desk with a heated keyboard, heated mouse, heated floor mat (designed for animal cages) and a warm incandescent light…

Heated steering wheels might seem like frivolities at first glance, but they're actually an important safety measure.

Lots of people drive with only the fingertips of one hand in the cold mornings because of cold steering wheels. Heating the steering wheel encourages the driver to keep both hands on the wheel, which is particularly valuable in winter when road conditions can be poor.

Re: Restoring the Old Way of Warming: Heating People, Not Places

#34

Earlier quoted context omitted.

It's pretty common around here (Copenhagen) for people to set their radiators to around 5-8 C (40-45 F) in rooms that they aren't using, or the whole house/apartment to that temperature if they're gone for more than a day or so, to save money on heating. Most radiators have a specific "frost protection" setting, indicated by a little snowflake icon, which is set by the manufacturer or building to whatever temperature…

I think as much as anything natural gas is cheap in the US. Does a house usually cool all the way down to 5 if you are gone for the day? A wood house definitely would (newer houses with better insulation might not, but many standing houses would).

No fuel source--apart from a wood- or coal-fired stove--is cheap enough in the US for folks in coldish climates to be indifferent to heating costs. Natural gas is probably the best deal right now, but lots of homes have oil or electric and it doesn't make economic sense to cut over the equipment. Also bear in mind a lot of the (populated, chilly) northeastern US's average housing stock is older than many other places.

Re: Restoring the Old Way of Warming: Heating People, Not Places

#35

3 Points: 1. Cars are moving into this with heated seats, and even heated steering wheels. Electric cars in cooler climates that don't have the excess heat production of an IC engine will depend on it to keep occupants warm. 2. There was an article a while back on HN about a fellow that had a computer desk with a heated keyboard, heated mouse, heated floor mat (designed for animal cages) and a warm incandescent light…

> 1. Cars are moving into this with heated seats

Moving into? I thought this has been commonplace for a while now? My parents 1991 model Volvo had heated seats. Maybe it's only common in colder climates.

Re: Restoring the Old Way of Warming: Heating People, Not Places

#36
post #33

3 Points: 1. Cars are moving into this with heated seats, and even heated steering wheels. Electric cars in cooler climates that don't have the excess heat production of an IC engine will depend on it to keep occupants warm. 2. There was an article a while back on HN about a fellow that had a computer desk with a heated keyboard, heated mouse, heated floor mat (designed for animal cages) and a warm incandescent light…

Heated steering wheels might seem like frivolities at first glance, but they're actually an important safety measure. Lots of people drive with only the fingertips of one hand in the cold mornings because of cold steering wheels. Heating the steering wheel encourages the driver to keep both hands on the wheel, which is particularly valuable in winter when road conditions can be poor.

This is actually even more important in cooler climates, where you may need to scrape the ice off of your car right before driving. Having frozen hands most definitely does not make driving easier.

Re: Restoring the Old Way of Warming: Heating People, Not Places

#37
At least in Japan and most parts of China, houses are poorly insulated and heating is often from aircon, which means if you want to stay warm, you wear thick clothes inside, sit under a heated blanket and what not.

This sucks.

Your nose and hands are still cold. If you want to move from the blanket its cold.

I don't see anything that really addresses this. Yeah, the insulated chair is nice when you sit on it, but what about when you need to get a cup of coffee?

Re: Restoring the Old Way of Warming: Heating People, Not Places

#38
I've seen some truly amazing things done with passive solar (i.e. building your house to optimally capture sun radiation and store it. The greenhouse effect on steroids.) Some houses in Maine don't have any heating system at all; they are built on certain inclines, angled just the right way, with ideal ratios of windows to insulation. In some cases, large stones are strategically just inside the windows to retain and slowly release heat.

It requires an esoteric expertise, lots of charts and graphs, and freedom to customize your plot of land. But it's awesome.

Re: Restoring the Old Way of Warming: Heating People, Not Places

#39

Motorcyclists provide an interesting example of this principle. The extreme windchill experienced by motorcyclists makes it very difficult to keep warm - a rider travelling at 70mph at 0°C experiences a windchill of -18°C. Many riders in northern climates use electrically heated underclothing, which, in conjunction with an insulated outer layer, can keep a rider warm with just a few watts. Better battery technology c…

In Rarotonga in the winter months you can buy puffer jackets with copper wiring sewn to the inside with a 9V battery.

Very cool....how long does it last?

Re: Restoring the Old Way of Warming: Heating People, Not Places

#40
post #3

This sounds like a good idea until mold starts growing in your house. Back in the day the houses were not insulated as tightly and people did not shower every day.

Depending on the exact climate/heating system, the energy saved might be enough to run a dehumidifier and still come out ahead. The dehumidifier will also raise the air temperature.

Recently, I've been wondering why we use exhaust fans in bathrooms and not dehumidifiers. I might be way off base here, but it seems like taking conditioned air that's a little moist and dumping it outside and replacing it with drier unconditioned air would be less efficient than just removing the moisture from the already-conditioned air.

I imagine it isn't one of those things where it's "always cheaper to do X", but there's probably a break-even point. Does anyone know how to do the math to draw that chart?

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