Dim Lights And Low Mains Voltage

[PatientlyWaiting]

I definitely agree ...

However, there is a lot of psychology at play, when you are talking about lighting.

Different people will have different perceptions of exactly the same lighting.

Good lighting, for me, is dependent on what I am doing, who I am with, what time of day it is, the decoration of a room, the outside light levels etc ...

As an example, it is surprising to me, how much affect gradually reducing the light intensity in my living room, starting about 2 hours before going to bed, has on the quality of the sleep I have - I will generally get to sleep quicker, be a lot less restless and feel more refreshed in the morning ... conversely, when I wake, I will try to expose myself to as high light intensity as possible, to ensure I fully wake - either a stroll to the shops or reading the newspaper outside, if possible, before heading off to work.

What I am saying, is it is about utilizing light in the most appropriate way ... I don't think attempting to emulate sunlight 24 hours a day is healthy for humans, who haven't evolved to cope with any lighting other than the sun yet.

We are not troglodytes. Good lighting, not necessarily bright, brings colour and atmosphere. Dull, cold low energy bulb light saps the human spirit.

I also prefer sunny days to grey overcast days. Is that unusual?

p-o-p

Edited March 2, 2008 by PatientlyWaiting

[surfcat]

Global cooling is world-wide and has dropped global temperatures by 0.65 - 0.75 oC. See some nice graphs here:

http://wattsupwiththat.wordpress.com/2008/...past-12-months/

January 2008 - 4 sources say “globally cooler” in the past 12 months

Not this ******ing crap again. Jan 2008 WAS cooler than Jan 2007 as indicated in the graph on that page because Jan 2007 was an El Nino (warm east Pacific Ocean and well correlated with global mean temperature) and Jan 2008 was a La Nina (the opposite). This is perfectly normal system of variability that has been going on for thousands of years, just like the similar El Nino peak at the start of 1998, followed by cooling.

[Jonesy]

I found it was only 213V at around 7pm, and has risen again to 220V by 11pm.

I wonder if this is a symptom of

1) A lack of power generation in my area (Southern Hampshire)

2) A lack of investment in transmission and generation (thanks to the privatisation)

3) The generators finding fuel (gas) expensive and thus turning down the voltage to limit power consumption??

I'd say no to all 3:

1 - The grid is pretty robust, supplies are not dependent on particular power stations operating besides if this did occur you'd hear about it.

2 - Could have been a problem with the wider distribution network but unlikely to be due to generation/transmission - there wasn't a NISM (notice of insufficient system margin eg. too little generation) announced. Besides lots of money has been poured into new generation since privatisation.

3 - No, the grid voltage is set and maintained by National Grid and would only be lowered under exceptional circumstances. Generators always look to run their lowest cost plant first so during periods of high gas prices you get a shift to coal fired plant. Ultimately though because gas generation is now a significant part of the total there will always need to be some gas plant running and the generator will have no choice but to run the plant and pass the costs onto the customer - hence what we're seeing with electricity prices at the moment. Plus it's not just gas prices that are rising, coal has gone up quite a bit as well.

The change in voltage is most likely due to volt drop across the substation transformer and cabling, the volt drop is proportional to load current hence why the supply voltage rises in the evening as the load on the TX and cabling falls as people go to bed and switch off lighting, appliances etc. I don't know why the voltage is relatively low - it could be an issue on the distribution network feeding the substation, it could be that the transformer is set on the wrong tap.

[pmgdawau]

It is the frequency which is affected by stress on the grid. If a station trips then the frequency drops. There is a real time chart on the National grid website.

Low voltage effects are likely to be local infrastructure related.

[Kurt Barlow]

Al the more reason to invest in oil and gas

But before that invest in personal efficiency- safer better return and the money grubbers get less of a slice.

[Kurt Barlow]

I'd say no to all 3:

1 - The grid is pretty robust, supplies are not dependent on particular power stations operating besides if this did occur you'd hear about it.

2 - Could have been a problem with the wider distribution network but unlikely to be due to generation/transmission - there wasn't a NISM (notice of insufficient system margin eg. too little generation) announced. Besides lots of money has been poured into new generation since privatisation.

3 - No, the grid voltage is set and maintained by National Grid and would only be lowered under exceptional circumstances. Generators always look to run their lowest cost plant first so during periods of high gas prices you get a shift to coal fired plant. Ultimately though because gas generation is now a significant part of the total there will always need to be some gas plant running and the generator will have no choice but to run the plant and pass the costs onto the customer - hence what we're seeing with electricity prices at the moment. Plus it's not just gas prices that are rising, coal has gone up quite a bit as well.

The change in voltage is most likely due to volt drop across the substation transformer and cabling, the volt drop is proportional to load current hence why the supply voltage rises in the evening as the load on the TX and cabling falls as people go to bed and switch off lighting, appliances etc. I don't know why the voltage is relatively low - it could be an issue on the distribution network feeding the substation, it could be that the transformer is set on the wrong tap.

I tend to agree with the above for now although I beleive we are moving towards the 'energy cliff' - 2012-2015.

If we were really near blackout / brownout time at peak demand points the National grid / govt would be running TV campaigns to reduce unecessary consumption at these critical times.

[needle]

Al the more reason to invest in oil and gas

Investments arent going to warm your house or cook your food though, are they?

[huw]

Investments arent going to warm your house or cook your food though, are they?

Try to buy a house before TSHTF, then you can install some kind of LPG cooking system and keep a couple of bottles of gas on hand

Even if you live in a flat with a balcony I suppose you could get a gas barbecue, much better than nothing...

[@contradevian]

Currently 242 volts here in East London, where energy density is an issue.

Also can remember the "voltage reductions" of the 1970's which resulted in reduced width and height on the ( largely thermionic ) TV sets of the time.

[Kurt Barlow]

Currently 242 volts here in East London, where energy density is an issue.

Also can remember the "voltage reductions" of the 1970's which resulted in reduced width and height on the ( largely thermionic ) TV sets of the time.

The site below gives real time health od the grid. I wont explain - its self explaintory if you go to the site

http://www.dynamicdemand.co.uk/grid.htm

[huw]

The site below gives real time health od the grid. I wont explain - its self explaintory if you go to the site

http://www.dynamicdemand.co.uk/grid.htm

I can't quite tell why, but that is very cool.

Edit: it leads to all kinds of interesting ideas: fridges, freezers, water heating, battery charging, even computer underclocking could benefit from dynamic power demand management.

Edited March 2, 2008 by huw

[Kurt Barlow]

I can't quite tell why, but that is very cool.

Edit: it leads to all kinds of interesting ideas: fridges, freezers, water heating, battery charging, even computer underclocking could benefit from dynamic power demand management.

Demand management is one hell of an effective way of helping integrate renewables into the grid. The dutch are already doing it with industrial cold stores. If people at home had smart meters they could be linked to things like immersions, washing machines, dishwashers etc

Edited March 2, 2008 by Kurt Barlow

[kagiso]

Not this ******ing crap again. Jan 2008 WAS cooler than Jan 2007 as indicated in the graph on that page because Jan 2007 was an El Nino (warm east Pacific Ocean and well correlated with global mean temperature) and Jan 2008 was a La Nina (the opposite). This is perfectly normal system of variability that has been going on for thousands of years, just like the similar El Nino peak at the start of 1998, followed by cooling.

Reply on the global cooling thread:

http://www.housepricecrash.co.uk/forum/ind...st&p=995055

[huw]

Demand management is one hell of an effective way of helping integrate renewables into the grid. The dutch are already doing it with industrial cold stores. If people at home had smart meters they could be linked to things like immersions, washing machines, dishwashers etc

I've thought about this idea before (in fact I think we've discussed it) but I thought some signalling mechanism would have to be designed, I didn't realise the frequency could be used. Can it really be the same frequency over the entire grid?

[MarkG]

Understand that the summer in Oz and Nz has been unusually cold this year.

Our winter has also been unusually cold. Most days have been below the seasonal average and one wasn't too far off the record low for the city.

But don't worry, I'm sure it's all caused by 'global warming' and banning supermarket plastic bags will save us.

[Kurt Barlow]

I've thought about this idea before (in fact I think we've discussed it) but I thought some signalling mechanism would have to be designed, I didn't realise the frequency could be used. Can it really be the same frequency over the entire grid?

Demand management is always going to be preferable to storage (pumped, compressed air or batteries) because their are less energy change shifts. I dont know how efficeint Dinorwic is but I bet its no greater than 80%.

It would be fairly easy to build a smart meter which has a radio reciever which tells the meter to energy a cheap rate circuit. From this immersion, heaters, heat pumps, battery charging could be performed. The signal could then be controlled by the NG to demand ballance the grid.

[tiggerthetiger]

Im going out side to chop more logs

[eightiesgirly]

When I was a very poor student nurse we would all wrap up in sleeping bags and lie on the couch watching tele. If it was very cold we added a beanie hat. Going to bed was easy, just jump in bed sleeping bag and all.

Looks like I might be digging them out again.

[homeless]

When I was a very poor student nurse we would all wrap up in sleeping bags and lie on the couch watching tele. If it was very cold we added a beanie hat. Going to bed was easy, just jump in bed sleeping bag and all.

Looks like I might be digging them out again.

and student nurses get paid more than any other apprentices out there.

infact student nurses get more than minimum wage jobs

oh how we laughed as we jumped into our sleeping bags

[homeless]

Im going out side to chop more logs

i just stuck a few more peats on the fire

heats the water too, which in turn circulates through the central heating

cost = 2 days hard graft per year

open fire+ hot water+ warms all the rest of the house via radiators

sorted

[Guest Bart of Darkness]

If we were really near blackout / brownout time at peak demand points the National grid / govt would be running TV campaigns to reduce unecessary consumption at these critical times.

Anyone remember those "Save It" campaigns of the early 70s. There was even a poster in my junior school IIRC.

[Kurt Barlow]

i just stuck a few more peats on the fire

heats the water too, which in turn circulates through the central heating

cost = 2 days hard graft per year

open fire+ hot water+ warms all the rest of the house via radiators

sorted

Burn it in a stove - you will get as much heat for about 25% of the effort!

[Sonic the Hedge Fund]

Demand management is one hell of an effective way of helping integrate renewables into the grid. The dutch are already doing it with industrial cold stores. If people at home had smart meters they could be linked to things like immersions, washing machines, dishwashers etc

This is allready being done in the UK, it's called 'frequency response'. Users include cold stores, smelting works, and sites with their own standby generators such as hospitals, data centres. Frequency response customers get cheaper electricity in return for having an 'interuptable' supply. When load exceeds grid capacity frequency response users are dropped, reducing the load for up to 2 mins while 'fast response' power is called up.

'Fast respose' generation includes OCGT and Diesel sets (often standby plant in hospitals, factories, IT centres etc.) that can be brought online within 2 mins, but is typicaly less efficient than propper base load plant. 'Fast response' plant therefore normaly only runs for up to half an hour, giving enough time to start base load plants to bring the grid up to the required capacity.

Edited March 2, 2008 by Sonic the Hedge Fund

[DEATH]

I am willing to do my bit and help keep a couple of student nurses warm.

[Guest Bart of Darkness]

I am willing to do my bit and help keep a couple of student nurses warm.

Altruism in it's purest form.