Crazy economics - negative pricing

[Dave2002]

Generally we are used to positive prices - we have to pay to obtain goods or services. In general life we don't experience negative prices.

It turns out that in wholesale markets there may indeed be negative pricing. I think that last night some electricity supply companies were offering negative prices - in other words they were paying consumers to use electricity they supplied.

There are some odd explanations for this, but surely as a general rule this is crazy - though might make sense in some situations.

Otherwise we know that some people would exploit this in unintended ways, as happened with the grants in Northern Ireland for heating up barns etc. It probably wasn't intended that people would get a benefit from heating up empty barns, but that is exactly what happened. The more heating they used, the bigger the payback.

Negative pricing may also be a feature of airline routes based on hub networks - though arguably there are vaguely sensible reasons for that.

[oddoneout]

As the oversupply of 'green' electricity at certain times is set to continue presumably more businesses will do what this one does? https://octopus.energy/agile/ Isn't it one of the selling points of smart meters?
There are also arrangements for some operations to mop-up such surpluses I believe - refrigeration in food companies for instance - which is presumably made to be financially advantageous to encourage uptake.

[Serial_Apologist]

When all energy supplies come from re-usables, this particular incentive will be ended, I predict.

[Bryn]

When all energy supplies come from re-usables, this particular incentive will be ended, I predict.

Perhaps we should construct a few more Dinorwigs to store such excess energy production?

[Dave2002]

Perhaps we should construct a few more Dinorwigs to store such excess energy production?

I think from what I remember, Dinorwig stores at most an hours worth of supply. There is also at least one similar, but less well known one, in Scotland.

[oddoneout]

When all energy supplies come from re-usables, this particular incentive will be ended, I predict.

Re-usable energy, now there's a thought.
I'm not sure the incentive will end, although it might take a different form. Currently generators are paid to stop generating when there is oversupply. A more constructive approach obviously would be to find a use for the surplus, but given the unpredictable nature of it some financial inducement is going to be necessary one way or the other I would have thought.

[oddoneout]

Perhaps we should construct a few more Dinorwigs to store such excess energy production?

Push ahead with domestic scale battery technology?

[Dave2002]

Re-usable energy, now there's a thought.

An interesting one, indeed.

Of course - there's seemingly no such thing. Energy use generally results in some loss, most likely in the form of heat. We think that "using" energy usually results in a loss of mass, by Einstein's formula and generally this loss is irreversible. Entropy never decreases over time, according to the second law of thermodynamics. Energy can be stored, which again by Einstein's formula, should result in a small amount of mass being generated - but even though that should happen, entropy will still increase in the process. The generated mass wlll eventually be converted back into what we call energy, so it's usually only a short term mass generation.

What some people often refer to as reusable energy is really energy from a source which is external to the earth, such as the sun, which for current practical purposes might be considered as a near infinite resource. Of course it isn't really infinite, but very large. Nuclear energy, generated on earth by use of various forms of radioactivity, might also be considered as reusable - but again it isn't really, though very large amounts of energy in forms which can be useful to humans can be generated by using nuclear generation, allbeit with some significant hazards.

Two forms of electricity generation - solar PV and wind generation, are both effectively tapping into energy sources external to the earth over which we have virtually no control - energy from the sun. We can however try to capture it and store it for use at times more convenient to us. That's really just a kind of energy time-shifting.

Another source of energy is due to gravity, and the interaction between the earth and other celestial bodies. Appart from the sun, the moon causes daily variations in sea level, which enables us to convert the motion of water into electricity. One other form of solar energy is used for direct use of heat, for heating water and other objects. This does not generate electricity, but is a means of getting some activities done - hot water for washing for example, or high temperatures for cooking.

Current technology allows us to store energy for relatively short periods, and then "use" it later. Some energy uses are considered more helpful to us than others. A simple example might be the use of heat and light for growing plants in an effectively - or partially - indoor environment. This can be done to create food which would otherwise be impossible. Similarly, animals can be kept alive over winters which would otherwise kill them.

Terrestrial radio active sources are interesting, because they represent a form of energy stored millions of years ago in massive supernovae events, though they also present significant threats if used unwisely or carelessly.

[oddoneout]

A simple example might be the use of heat and light for growing plants in an effectively - or partially - indoor environment. This can be done to create food which would otherwise be impossible.

This is something which I think well worth pursuing. There are some very interesting projects around to produce food in non-agricultural settings, such as the converted containers which have a glasshouse on top of a hydroponic unit and can produce fish and veg in city centres. There is an obvious role for such ideas, which some permaculture projects are beginning to set-up, in providing food for the likes of refugee camps. Despite the hightech appearance, in many cases they are much lighter on resources(water in particular) than alternative methods of producing the same quantity of food, and can have very much lower requirements for pesticides etc.
I can't find the container example just now but this is one take on such alternatives where surplus renewable generation could be put to good use? http://growing-underground.com/
This is an ongoing project https://www.somethingandson.com/work/farmshop

[Dave2002]

Push ahead with domestic scale battery technology?

I'm just trying to get a handle on this idea, and if it's really worthwhile. Long term - probably yes - about 100 years.
Short term, maybe not, though if there was real political will, then maybe.

You might find this website interesting - https://gridwatch.co.uk/ - it really is VERY interesting. About now this shows UK demand on the grid at about 35 Gwatts.

A Tesla home battery stores I think up to 70 kWh - similarly for the batteries in the Model 3. Something like a Renault Zoe battery stores about 45kWh.

Suppose every battery owned by a homeowner or car owner in the UK was available to return electricity to the grid. What would be a reasonable rate of return?
Let's suppose that everyone agreed to have 1% of the stored energy returned to the grid at periods of high demand, or if there was a temporary or complete grid failure.

My rough calculations suggest that around 850,000 batteries would be needed under these conditions to sustain the whole UK network for 1 second. The installed cost of a Tesla home battery is of the order of 7-8 thousand pounds, so the total "investment" would have to be about £7 billion in order to provide resilience for a 1 second complete grid shutdown.

An estimate of the total GDP/"value" of the UK is around £400 billion per annum, though I treat such data with considerable concern. This suggests that even if all the UK's efforts were directed towards installing batteries in one year, - ignoring everything else, including power station construction, operation and maintenance, and everything else which would normally have to be done, that even one year's such work would only achieve a total resilience of just under one minute.

In practice it would probably not be necessary to safeguard against a complete grid shutdown, and investments could be spread over many years, but the point I'm trying to make here is that the scale of operations would be really large.

If end users were (on average) willing to allow 50% of their stored energy to be used, then maybe a 20-25 second shutdown could be accommodated - based on the assumption that around half of the batteries would be only half max capacity - on average.

Ideally of course complete failure requiring large quantities of electricity to flow back to the grid wouldn't happen, and failures would be localised, and end users could use up "their own" stored electricity, rather than returning it to the grid. That would be a much more practical way to cope and would require less complicated technology solutions.

It might also be interesting to compare the short term effectiveness of a battery scheme with Dinorwig. Dinorwig can supply a maximum power of 1,728-megawatt (2,317,000 hp) and has a storage capacity of around 9.1 GWh (33 TJ).