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Hi Patrick & All,
DIGRESSION
Some may object that we are getting off topic. If so then I hope it =
will be possible to disagree in a civil manner. In my view, the =
activities of humans directly or indirectly affect the natural world to =
a much greater degree than all other factors combined; in round numbers =
our effective impact would be at least 100:1 and perhaps as great as =
1000:1. The central question is now and always will be; how can human =
activities at the local and the global level be modified in acceptable =
ways so as to decrease our impact on the natural world ?=20
Nothing said on natureNS will directly reverse this massive and =
accellerating destruction but it might be possible to germinate ideas =
which would in time start to diminish human effects locally.
END OF DIGRESSION
The LED is great for outdoor use; no question. And yes, outdoor =
lights which may be on for appreciable periods, should be directional =
and aimed downward.=20
The 90+% efficiency of oil heating may also be an illusion in many =
homes where heat will be directed to all parts of the house (usually =
near the exterior walls/windows where the heat gradient will be maximal) =
whether the rooms are occupied or not. Oil may be 90% efficient at the =
furnace but less efficient overall if rooms not occupied are heated. =
Conversely light bulbs, for the reasons you advanced and I had not =
previously taken this into account, may currently be only about 45% =
efficient in total (light + heat) in a given room but somewhat more =
efficient overall when the small heat supplied by lights in occupied =
rooms is such that oil is not required. [So far this fall I have had =
the radiators on for a total of about 2 hours; largely a wood effect but =
lights likely decreased the need for wood initially.]=20
The need to burn fossil fuels for power generation is man-made. It =
is a product of history, inertia and indifferent or inept management. =
And much of that waste heat of spent steam (not sure how much) can be =
salvaged by using it for space heating and water heating for nearby =
commercial or residental buildings, stored underground for later use =
and used to heat nearby greenhouses.
Wind and water could produce nearly all of our electricity if the =
will were there to do it. Because our governments have fumbled the wind =
generation ball it is a real mess; 26 different sets of standards for =
setback (if I recall correctly) in NS alone and these change at the whim =
of fear and rumor.=20
One thorough study and analysis of turbine setbacks by e.g. the =
National Research Council (before it was made threadbare by 50 years of =
cutbacks), with ongoing refinements as turbine designs change, would =
have given all concerned, industry and homeowners, the guidance to move =
forward with confidence. And of course greatly simplified the approval =
process and reduced the cost of establishing wind farms. It still needs =
to be done.
The wind does not blow all of the time but that is no problem =
provided sufficient wind energy were used to pump water to reservoirs at =
high elevation so hydroelectric generation could act as a backup during =
periods of calm. This approach has been used successfully at several =
locations for decades and we have ideal topography/geology. The same =
water could be recycled many times and doing so would provide backup =
irrigation water for agriculture and if done prudently would tend to =
improve streamflow stablilty.=20
Solar energy and generation of power from waste are two additional =
approaches which are as yet barely tapped here. A recent newspaper =
article (2014 ?) featured generation of power from cow manure sufficient =
to supply all electrical needs on a fairly large farm with surplus to =
sell; at a profit sufficient to clear the investment in 10 (?) years =
with a by-product of use as a soil amendment and of course the bonus =
effect of decreasing release of methane. The same could likely be done =
with doggy do, human waste and perhaps even fermentable organic waste if =
waste disposal were adapted for this purpose.=20
=20
----- Original Message -----=20
From: Patrick Kelly=20
To: <naturens@chebucto.ns.ca>=20
Sent: Wednesday, December 17, 2014 9:58 PM
Subject: Re: Long: Re: [NatureNS] light
There is a complicating factor on the idea that the heat from the =
incandescent bulb now needs to be replaced by another source. Most =
electricity in Nova Scotia is still generated by burning fossil fuels. =
In large power stations, heat losses and inefficiencies in the steam =
turbines mean that of the 100% of potential energy in the oil or coal =
you lose about half of that right off the top. Transmission losses can =
easily use up another 10%.
http://www.mpoweruk.com/energy_efficiency.htm
From an environmental point of view, you would be better off have an =
oil furnace and getting your heat at 90+% efficiency.
From an astronomer's viewpoint, the big advantage of outdoor LED =
lights is that to reduce the energy use in the luminaire, you have to =
put the light only where it is needed, reducing CO2 emissions, glare, =
light trespass, and light pollution. I cringe at night when I pass by =
houses or businesses that have wasteful lighting that serves to useful =
purpose. The test for this is quite simple. Walk around your property =
line at night. If you can see the bulb/filament, you have a problem.
But, yeah, the way the government did handled the whole thing left a =
lot to be desired.
Sent from my iPad
On Dec 17, 2014, at 9:32 PM, "David & Alison Webster" =
<dwebster@glinx.com> wrote:
Hi Rick & All. Dec 17, 2014
I didn't notice that slip but would not have been disturbed by =
it in any case. Newspaper articles are not intended to be the full story =
in technical matters; words get dropped in draft or in editing. It is my =
understanding that they contain mercury vapor, vapor will be distributed =
throughout the volume of the tube, so mercury-vapor filled if you wish.
I was more interested in the background of this scam. From the =
start I concluded that replacing incandescent bulbs with CFL bulbs would =
not conserve significant energy under our conditions. And when LED bulbs =
arrived in the market I concluded that the same applied to them. And I =
object in principle because what is so wrong with freedom of choice in =
the marketplace ?=20
Correct me if I am mistaken, but it is my understanding based on =
the conservation of energy that consumed electricity will be converted =
to either light or heat (neglecting the tiny electromagnetic radiation =
which I expect might be generated when a switch contact is made or =
broken and the energy required to heat the filament initially for << one =
second). Except for very brief unusually hot periods in summer when long =
daylight hours decrease the nee