wrote:
To justify mandating widespread use of cfls one would need to
establish all the following:

It is only necessary to establish that there is a risk that severe
effects will ensue in order for it to be worth avoiding. The reason
for this is that the effects are likely to be so severe as to make any
costs incurred avoiding them to pale in comparison,

1. climate is changing

True

2. the change is caused by CO2 emission

CO2 is involved - to state it as the only and sole cause would seem a
little rash.

3. this change will be seriously destructive

Possibly true, but what is not established is whether the costs of
attempting to prevent such change are not going to be greater and more
destructive than attempting to adapt to it should it occur.

All of these are very well established. In particular CO2 is very

Only if you swallow the party line...

well known to cause global warming and the mechanisms and the size of

The new PC lingo is "climate change" - global warming seems to have
stopped.

the effects are very well understood.

The effects are not at all well understood.

4. The only way to reduce CO2 emission is to reduce energy use

No, any way of reducing CO2 will reduce global warming and all
avenues including energy reduction should be pursued,

Doing nothing (looking at the big picture) also currently seems to be
preventing global warming.

5. the 0.1% energy saving that switching to cfls will give us will
make a real difference

A 0.1% energy saving will save 0.1% of energy. The advantage of

Will it? That seems unlikely since the cost of swapping to the new
technology is not zero. Every lamp fitting, or dimmer switch that needs
to be replaced erodes the energy saving.

changing lightbulbs is there is no downside whatsoever and so
obviously it is a good thing to do.

There are a multitude of downsides - frequently discussed.



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/