Christmas tree power consumption

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TANE
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Christmas tree power consumption

Post by TANE »

How much power is your Christmas tree consuming?

100 lights 48,1 watt

[img]uploaded/Chak/2008121216277_christmas_tree.gif[/img]
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Noel
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Christmas tree power consumption

Post by Noel »

Thats private info :-)
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Christmas tree power consumption

Post by rwitkamp »

I agree WiFi! ;-)

Now he wants to know about our Xmas trees, what will be next? ;-)
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TANE
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Christmas tree power consumption

Post by TANE »

Don't worry I'm not going to sell any products to you.
this topic was just to think about alternatives.
all the lights looks wonderful and can be in the future
I was wondering if someone is using leds or others lights.
Most of the households in the Netherlands consume about 50 KW power for Christmas lights.
This can be reduces to less than 1 KW if we go for leds
At the end we will still have wonderful Christmas and save lot of energy.
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Noel
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Christmas tree power consumption

Post by Noel »

We are still old school. We use candles in our tree!
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Christmas tree power consumption

Post by rwitkamp »

You're right Chak. I planned to buy Led lights next year. Hopefully the prices will become lower then. This year I still use some of the old fashioned ''bulbs' and I realize it is not very efficient. A quick calculation brings me to 150 Watt power consumption for lets say 8-12 hours a day.
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Christmas tree power consumption

Post by Pieterpaul »

I am always for saving energy and I surely don't want to spoil the (Christmas) party, but the additional power used by (indoor) chirstmas lighting is not really lost, it just heats up your house a bit. With the weather we have currently, this is not much of a waste. There may be a little efficiency difference between using oil or gass to heat up your house and using electricity, but the difference is very small at best. And if you look at CO2 exhaust electricity might even be the better solution (as it can be generated from wind, sun or nuclear fusion).
Assuming next year's Christmas does not happen during a heatwave, the only gain you have with the LED lights is for outdoor use.[:o)]
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Christmas tree power consumption

Post by Lennart »

Hi Pieterpaul,

Although I agree that electricity from renewable sources (wind, solar and hydro, but *not* nuclear) is to be prefered over any other source of energy, I have to correct you on this statement:

"There may be a little efficiency difference between using oil or gass to heat up your house and using electricity, but the difference is very small at best."

Power plants fueled by gas have a typical efficiency of only 40 to 60 percent. Add the loss in power transportation (around 10 percent), and the "little efficiency difference" of your "heating by Christmas lights" scheme adds up to 46 to 64 percent. (As modern central heating systems have an efficiency approaching 100 percent.)

Even more interesting:

If you are using your 5% efficient Christmaslight, 95% of power consumption is transformed into heat. If the power plant that generated your electricity is an "average" power plant using gas as its fuel, its efficiency, including transportation, would be around 45% (50% * 0.9). Each kWh of energy that is stored in gas will generate 0.45 kWh of electricity and thus 0.428 kWh of heat in your home (the other 0.022 kWh is used for the Christmas lights). So heat efficiency is around 43%.

Now compare that to a modern locally installed heating system using earth tubes (bodemwarmte), with a COP of 5 (generating 5 units of energy for each unit of energy consumed by the heat pump). If it is running on locally produced solar energy, it will generate 5 kWh of heat in your home for each kWh of solar energy generated. Its efficiency is thus 500%. Or 11.6 times that of your Christmas lights heating scheme. Let's say 11 times, so you can use the remainder to run all the LED lights you'd ever like in your Christmas tree.

So much for "the difference that is very small at best".

Lennart
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Post by Noel »

As a new experiment I'm now using the electricity from the phone like to power my lights.
Only problem now is that when someone calls the lights start to flash :-)

Not sure who is paying for this electricity, but I do not think that this is me.
Next experiment will be powering my Eee box.

(the above message is a joke)
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Jeroen Bartels
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Christmas tree power consumption

Post by Jeroen Bartels »

@wifi:
Ehhh, that's not saving energy, that's stealing energy. Maybe you live next to snelvuur's friend (http://www.domoticaforum.eu/topic.asp?TOPIC_ID=1920) as he is leaking 5000kwh/year. Maybe you hooked up your dryer and washing machine to his yard lights wiring....




(Joke also ;-)
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Christmas tree power consumption

Post by Pieterpaul »

Hi Lennart,

I'll agree with you that my statement about the difference in efficiency being "very small at best" is somewhat of an overstatement. I'll also agree with you on the numbers of efficiency of the power plant (for producing electricity) and the heating system. However, the rest of your story does not make much sense to me.

First of all, I explicitly mentioned nuclear fusion (not fission!) as potential energy source, which is probably as efficient (and clean) an energy source as they get.
Secondly, the whole efficiency issue is inevitably tied to impact on the environment: I presume Chak and others are not out to increase efficiency per se, nor to save electricity or gass just because it is fun; they just want to do something that is better for the environment. One could argue whether 20% efficiency of otherwise clean and renewable energy (say hydro power) is really worse than 99% efficiency of oil or gass burning heating systems.
Third, if you want to compare full chain-efficiency (like you do for electricity), then you have to do that for all your examples. With gass-operated heating systems, you need to distribute the gass to all houses. That does not happen without leakage nor without (energy consuming) pumping stations. Also, the efficiency loss of the power station is loss in terms of electricity production. The remainder ('waste') can be used for heating houses (as is done in some places), and some of the produced gasses (CO2) can be fed into greenhouses (as is done in the 'Westland' in NL) in order to stimulate crop crowth. I have no idea how to incorporate that into the efficiency equations, but it is surely something that is very difficult if not impossible to do with the fumes coming from every house. You'll still end up with higher efficiency for the heating system, but it's less than 50% difference.
Fourth, there is the possibility of using a fuel cell to generate both heat and electricity right in your house. If you compare its efficiency to that of the gass operated heating efficiency is even closer to 100%. Using light bulbs or LEDs in such a case make zero difference.
Finally, reaching a 500% efficiency level defies all laws of physics, as it would mean that you generate more energy than was originally available. You can only reach such a number if you choose your system-boundaries incorrectly (or wisely, depending on who you want to persuade [:)]). An analogy for such a miscalculation would be to look at a solar panel. It just sits there, does not consume any energy, yet it produces a few kWh of energy, so it must have infinite efficiency [:o)].

Sorry, did not want to start a my-energy-is-better-than-yours war, and I certainly do agree that earth heat is a fine way of generating energy (be it electricity or heat). But moving your christmas tree to iceland for it is probably not very efficient [8D].

Regards, PP
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Christmas tree power consumption

Post by Lennart »

Hi Pieterpaul,

Thanks for your reply. Sorry about the remark on nuclear energy, I overlooked the *fusion* part and I fully agree on the potential of that technology (now if we could only achieve that at acceptable temperatures).

As far as your other comments go:

2) I agree that impact on the environment should be the leading factor, not efficiency "pur sang". On the other hand, generating renewable energy usually is not trivial in terms of technology and costs involved. And unfortunately this world seems to be mostly driven by money-based incentives. 99% efficient fossile energy would in the current situation definitely be less expensive than 20% efficient renewable energy. And in many cases it would be worthwhile to try to improve efficiency first instead of generating more (renewable) energy (to a certain point as improving efficiency also has costs associated with it that increase as efficiency improves). So yes, you're right that 20% efficient renewable energy is better for the environment than whatever-efficient fossile energy, but efficiency would play an important role in costs and thus acceptance. Even for Chak and others, as I think that - and please let them correct me if I'm wrong - costs is also a factor (not neccessarily the main factor) in their quest for lowering their power consumption.

3) Indeed, I did not take all factors into account for neither example. The gas example might be a little too optimistic, given leakages and energy costs of pumping. The electricity example might be too pessimistic given the use of "waste" heat in some cases. However, I doubt that it would considerably change the equation in the current situation. The *potential* of using this waste heat is enormous. In reality, most of it is literally thrown into the water (cooling water, that is). To quote a (Dutch) report on waste heat for the city councel of Amsterdam:

"Elektriciteitscentrales hebben een energetisch rendement van 50%. Dit betekent dat slechts de helft van de primaire energie (gas, kolen etc) in elektriciteit wordt omgezet, de andere helft wordt als restwarmte geloosd. In Nederland bedraagt de totale hoeveelheid ongebruikte restwarmte jaarlijks een equivalent van 15 miljard m3 aardgas, of 525 PetaJoule (PJ). Deze hoeveelheid is gelijk aan 1/3 van ons jaarlijkse aardgasgebruik. Met behulp van een warmtenet kan deze restwarmte nuttig worden gebruikt."

and

"In absolute getallen: de totale primaire energievraag bedraagt 3.300 PJ; de warmtevraag 1.300 1500 PJ, en de warmtevraag in de gebouwde omgeving ongeveer 500 PJ. De hoeveelheid restwarmte (525 PJ) is dus theoretisch hoog genoeg om de gehele bebouwde omgeving in Nederland van warmte te kunnen voorzien. [...] Momenteel zijn er in Nederland slechts 270.000 aansluitingen op warmtenetten."


4) The efficiency of local fuel cell technology (micro-WKK or HRe as the Dutch call it) is indeed closer to 100% than for your regular high efficiency gas heater. If you are using this technology to generate all of your electricity locally, then indeed, heating by Christmas bulbs would be equally efficient as (or even a little better than) heating by gas.


5) 500% efficiency within a closed system is, as I hope we all know, indeed not possible. However, the system is not closed (nor required to be), as the energy is coming from the earth. As I said, using a heat pump, you need to invest 1 unit of energy into the pump to get 5 units of energy from the earth. Sure, it might not be completely fair to talk about efficiency of the system in that case as the system is open ended, but that's my choice :-). The point I wanted to make with the earth heat example, however, is that there are better ways to invest your kWh - regardless of how it got generated in the first place - than using an electrical heater (or bulb). BTW the technology is readily available, even in the Netherlands, at low earth temperatures. No need to move your Christmas tree to Iceland in search for geothermic activity! (Though Iceland is very nice... :-)

No my-energy-is-better-than-yours wars as far as I'm concerned. After all a Joule is a Joule, in whatever form, be it gas or electricity or the Christmas dinner fat around ones body. I guess we only disagree on the efficiency of a kWh that comes from the grid at the end of the equation. And to me it's clear that your remark about heating by bulbs was not just a repeat of one of those popular media memes; you've thought it through a lot more thoroughly than I thought.

Lennart
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Christmas tree power consumption

Post by Pieterpaul »

Thanks Lennart,

I won't reply in detail to all your points, as I don't want to get into an endless discussion. We may have some differences on details, but I think in the end we are on the same page: Iceland is very nice [:D]

Regards, PP
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Christmas tree power consumption

Post by Lempens »

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by wifi</i>
<br />As a new experiment I'm now using the electricity from the phone like to power my lights.
Only problem now is that when someone calls the lights start to flash :-)

Not sure who is paying for this electricity, but I do not think that this is me.
Next experiment will be powering my Eee box.

(the above message is a joke)
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Christmas tree power consumption

Post by DJF3 »

Big tree, 60 lights, 180W. Now reduced the number of lights to 30 which still consumes 90W...
"Before" I wasn't really aware of that, now I really turn it of when it's not required.


Cheers
DJ
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