Comments on: AskPablo: Going up?

By: dglevy

dglevy — Sat, 03 Jan 2009 00:09:47 +0000

that white paper cited by william was really excellent. the author studied the subject in much greater detail than any of these web page authors have. but i would like to see where william gets that figure of a counter-weight equalling only half of carrying capacity. that makes no sense. it should counter-balance the exact weight of the cab, at the very least. but i'm just speculating here.

elevator energy consumption depends a LOT on the elevator type, as the white paper says. if you live in a low rise building (7 floors or less) you probably have a hydraulic elevator, which uses no counterweights and can use 3 times as much energy as a high rise 'traction' type elevator.

while an individual elevator trip does not account for much energy use, it adds up over the years. in my building, i generate about 6.5 kg of carbon emissions per year by taking the elevator. that works out to half a metric TON of carbon over a lifetime.

but the real point is this: americans--and increasingly other nationalities--tend to be overweight. if everyone at least took the stairs going DOWN, they would save tons of fossil fuels and lose weight in the process.

By: William

William — Fri, 13 Jun 2008 03:29:32 +0000

You do not account for several significant factors. The elevator is likely balanced for 1/2 of full carrying capacity, and this is never the exact case, so the total weight carried is the persons weight plus a portion of the weight of a very heavy elevator cab. The elevator is a “vampire device” that is always in standby and it constantly uses power, which could burn about 10,000 kw per year just siting there doing nothing. [ref: http://www.aceee.org/buildings/coml_equp/elevators.pdf
Also, you have to factor in the efficiency factor at which the system (motors, etc) is operating.

By: FK

FK — Tue, 22 May 2007 17:10:31 +0000

I also looked into this issue, and my calculations came to 2.5 Wh per floor vs. the 1.5 Wh calculated here. They are in the same ballpark, and still jive with the conclusion that elevator usage doesn't take very much energy.

By: Janis Mara

Janis Mara — Wed, 11 Apr 2007 20:14:13 +0000

Hey, that last part caught my eye – now that’s a great inducement to hit those stairs! I work on the sixth floor, just think how much calorie-burning activity I could add to my day.
I really appreciate the pointer to the Energy Ideas Clearinghouse, which is indeed a cool Web site. But it does seem mostly for use by energy professionals. Here’s my question:
Reducing my driving; using the same bag at the grocery store until it falls apart; recycling; replacing regular bulbs with compact flourescents. Which one of these has the most impact? I guess what I’m wondering is – what can I do, what change can I make, that would be the most significant in reducing global warming?
Since you were so kind as to answer Elevator Pete’s question, I’m hoping you’ll help with mine!
Janis Mara
http://www.ecotality.com