Hot weather, effects on electricity demand and production

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adam2
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Hot weather, effects on electricity demand and production

Post by adam2 »

A generally warming climate, combined with the present hot spell is having a noticeable effect on electricity consumption.

A look at the gridwatch site shows that electricity demand last week increased significantly if compared to previous weeks.

Peak demand still occurs in winter, often peaking at about 50GW, with demand reducing in the summer. Very hot weather does however increase demand beyond that existing in moderately warm weather.

Air conditioning no doubt plays a part in this, although still uncommon domestically, air conditioning is increasing demanded or expected in shops and leisure premises.
Individual fridges and freezers are of low loading, but tens of millions exist and they all use more energy in hot weather than cool weather.

Fridges used in pubs and bars are often of very low efficiency indeed. If they are installed in air conditioned spaces then more waste results.

Electric fans use very little electricity individually, but use of say 10 million of them is a considerable load.

High temperatures also affect electricity production, though to a lesser extent than in the past.
Output of steam driven power plants can be limited by high air or water temperatures, or in some cases by low river flows. This includes nukes and steam cycle of CCGT plant. The output of gas turbines is sometimes limited in hot conditions.
Hydroelectric output may be restricted by drought.
Wind and solar are not normally affected.


High temperatures also reduce the capacity of electrical transmission and distribution equipment, and increase resistance losses therein.

I see no cause for concern in the near term, meeting the winter evening peak demand is still the main challenge.
In the longer term problems may occur.
"Installers and owners of emergency diesels must assume that they will have to run for a week or more"
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PS_RalphW
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Post by PS_RalphW »

On the plus side, the relentlessly sunny weather has resulted in an 8 day record solar electricity run, and solar briefly exceeding NG at 2pm last Saturday, to become the biggest single source of electricity.

That despite the near total collapse in PV installations in the last year.
fuzzy
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Post by fuzzy »

I would guess the increase is due to more showers and washing machine use in very hot weather.
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Re: Hot weather, effects on electricity demand and productio

Post by vtsnowedin »

adam2 wrote:
Fridges used in pubs and bars are often of very low efficiency indeed. If they are installed in air conditioned spaces then more waste results.
You will have to explain that one a bit. First why a pub would buy an inefficient fridge and then why working in a already cool space makes it more inefficient.
Most Pubs I'm familiar with have fridges of the chest type which hold the cold air in when the top is opened instead of spilling out every time a closet upright type has the door opened. They fit nicely under the bar and a comely serving wench bending down to grab you a bottle gives you a nice view of her assets. :D
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adam2
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Re: Hot weather, effects on electricity demand and productio

Post by adam2 »

vtsnowedin wrote:
adam2 wrote:
Fridges used in pubs and bars are often of very low efficiency indeed. If they are installed in air conditioned spaces then more waste results.
You will have to explain that one a bit. First why a pub would buy an inefficient fridge and then why working in a already cool space makes it more inefficient.
Most Pubs I'm familiar with have fridges of the chest type which hold the cold air in when the top is opened instead of spilling out every time a closet upright type has the door opened. They fit nicely under the bar and a comely serving wench bending down to grab you a bottle gives you a nice view of her assets. :D
There two main reasons why very low efficiency fridges and freezers are popular in pubs and bars.
Firstly many such establishments are run from a very short term point of view, a fridge or freezer is often a "distress purchase" with least first cost being the main factor being considered. The saving of say a penny an hour if considered at all is regarded as utterly insignificant.
Secondly, a lot of bar fridges are supplied on free loan by brewers so as to promote their products, why would they care about the energy use ?
Most bar fridges in the UK are front opening with glass doors and are intended to display the contents in view of the customers.

Use of low efficiency refrigeration equipment in an airconditioned space increases the energy used by the air conditioning since it has to work harder to remove the extra heat produced.
"Installers and owners of emergency diesels must assume that they will have to run for a week or more"
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adam2
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Post by adam2 »

This is a typical beer fridge as widely used in the UK.
Fleabay link to show the TYPE of product to which I refer, and NOT by way of recommendation.

https://www.ebay.co.uk/itm/Kool-50ltr-C ... SwWkFafaMr

Note the absence in the listing of any efficiency or energy consumption data. But it is cheap and can be delivered quickly, what is not to like.
"Installers and owners of emergency diesels must assume that they will have to run for a week or more"
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Mr. Fox
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Re: Hot weather, effects on electricity demand and productio

Post by Mr. Fox »

adam2 wrote:Electric fans use very little electricity individually
Hmmm... Perhaps the basis for a new Government renewable energy initiative?

Image

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I'd estimate that the loss in efficiency of a front opening refrigerator compared to a chest type is more than offset by the lower air conditioning requirements that result from not having to remove the heat generated by pervy old men leering at the bar staffs' rear end as they go about the business of serving them.

In all of the pubs I know, use of the word 'wench' would further lower energy demand, as the person using it would rapidly find themselves sitting outside on the pavement, reducing air conditioning requirement even more. 8)
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Post by vtsnowedin »

OK to get back on topic sort of.
I have been working night shifts this week and the third night of it a thunder shower passed through right after I went to work. A lightning bolt zapped a power pole between my house and my daughters knocking out power for us and five neighbors. My wife called me at work to ask how to start the back up generator as she had never done it before. we got passed that but then found that I did not remember where I had left the extension cords necessary to hook up the essential devices in the house so she went up to the daughters house and borrowed a couple of her's.
Moral of the story is: have a few drills so everybody knows how to execute the backup plan and have all the needed parts stored in plain sight where people expect them to be.
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adam2
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Post by adam2 »

Electricity production from hydroelectric plant has been roughly halved if compared to a few months ago.
Not of great significance since demand reduces at this time of year and hydro power is a minor contributor to the UK grid.
"Installers and owners of emergency diesels must assume that they will have to run for a week or more"
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Post by kenneal - lagger »

I was running a cob earth building course at The Centre for Alternative Technology in West Wales last weekend and they have a water shortage there such that the normally potable water in the guest rooms is now a dirty brown colour from the sediment being stirred up from the bottom of their reservoir. This water also runs the cliff railway and their hydro generation. The railway is running but not the hydro.

I've been up to the reservoir loads of times in the past and even swum in it but that is now banned. The four foot drop in level is not so noticeable as the absolute quiet. Normally you can hear streams running and a small but high waterfall splashing. Not this time; just an eerie silence. And this is in an area that normally has well over a metre of rain a year.
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Post by fuzzy »

The Marches [Welsh Border] has seen almost no rain in 2+ months. Maybe a light shower every 3 weeks roughly. The severn trent levels are not too bad considering, although the pennines at 55% looks low:

https://www.stwater.co.uk/about-us/rese ... july-2018/

So it's not 76 yet [which started with 2 drier years]
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Post by kenneal - lagger »

On my way to CAT on Friday evening I got a good dousing in the Marches around Hereford. In the grand scheme of things it probably only wet the surface though.
Action is the antidote to despair - Joan Baez
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Post by clv101 »

I was up at CAT today, water shortages persist.
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Post by kenneal - lagger »

We've got a 50% chance of rain on Sunday, apparently. Can but hope!! We're running out of stored rainwater for the garden.
Action is the antidote to despair - Joan Baez
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Post by emordnilap »

It's raining fairly heavily now (Thursday) in the west of Ireland. I suspect we'll send some over to you shortly. :lol:
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