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Mains frequency

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Mains frequency

Posted by Kelly Marie on Feb 12, 2020 9:39 pm

Just checked the dynamic demand site and the frequency was down to around49.7 cycles almost down to the lower legal limit never seen that before

Re: Mains frequency

Posted by Jam on Feb 17, 2020 5:00 pm

Big batteries are over here too, doing the same thing. For example
https://stateraenergy.co.uk/Energy%20Storage%20Facility/pelham-storage/

...And in the August 2019 grid wobble, National Grid credited EFR/FFR providers which included batteries, with sustaining the frequency enough to avoid further outages.
https://www.nationalgrideso.com/information-about-great-britains-energy-system-and-electricity-system-operator-eso
To save you reading (final report, p4)

All the “backup” power and tools the ESO normally uses and had available to manage the frequency were used (this included 472MW of battery storage) to stop the frequency fall (at 49.1Hz) and being recovering it towards 50Hz.

As Simon Barker says, these plant are designed around a very short duty cycle, but also very fast response times, primarily to provide this function (normally less dramatically than the above event mind you). National Grid procures this service directly, just as it does other reserve services. It is not the same as long term storage, which would most likely be better suited to other technologies (flow batteries anyone?) that may struggle to react quickly enough to frequency events.

Lastly, worth looking at the requirements for G99... All mid-size generators (>1MW), including inverters, now have to incorporate a frequency response mode featuring a droop curve (albeit asymmetric, depending on size, but the point is it responds to network loading), plus feed in to / ride through close in faults, limited network voltage control and provide a DNO control interface.
https://www.energynetworks.org/assets/files/electricity/engineering/engineering%20documents/ENA_EREC_G99_Issue%201_Amendment_5_(2019).pdf

Re: Mains frequency

Posted by mapj1 on Feb 17, 2020 5:00 pm

What really comes out of that article about Australia, is not the battery at all, but rather just how dependent they are on coal - 5 out of 6 GW in New South Wales and Queensland, and 3.7 out of 3,8 in Queensland ! 
(NEM is not a state, it is a National Electricity Market, i.e the totals..  and 19GW total - is that really all  ?)
And given the space and climate how little they make use of either wind or solar.
regards Mike

Re: Mains frequency

Posted by OMS on Feb 17, 2020 5:18 pm

Coal is however cheap to mine, and they make a big profit exporting huge quantities of it - burning a bit along the way makes good economic if not environmental sense

However, the hard of thinking believe the recent fires are a warning from the sainted Greta to mend their ways  - who was it said, they have sown the wind and now shall reap the whirlwind - ahh yes, I remember now.

Regards

OMS
The trap we've fallen into is to believe that a thousand incompetents properly organized can do the job of a few dozen outstanding people

Re: Mains frequency

Posted by davezawadi on Feb 17, 2020 6:25 pm

Where are you Mike, there is little point in solar past Birmingham? Although it is often sold, the sun angle and latitude is the controlling factor and even southern England is not very good.
Regards David CEng etc.

Re: Mains frequency

Posted by Chris Pearson on Feb 17, 2020 6:59 pm

mapj1:
Well round here there are fields of the damn things springing up on every 1000 sq meter scrap of  land that would be too rough to plough and cannot get planning permission for a housing estate.

Well, that may be the best use of the land. Around here, a parcel of land has been isolated by the creation of a new road, but on the other side of the road there is already a solar farm. More panels may be somewhat unsightly, but they certainly beat the prospect of extra traffic which would negate the benefits of the new road.

Re: Mains frequency

Posted by Simon Barker on Feb 17, 2020 9:02 pm

davezawadi:
Surely this article is joking. a 44 MW help when GW are connected is not going to do much at all. I don't know what the total consumption in SA was, but probably not all that much. This is only about 1000 cars worth of battery, and it saved the day? I suggest it was the industrial load shedding of aluminium heating which really did the trick.
 

Another article says it's 100MW, storing 129MWh, but they are planning on upgrading it.  But that is just one battery bank.  You wouldn't try to run the entire country off one power station, and one battery bank wouldn't serve the whole of the UK either. https://www.smh.com.au/business/companies/huge-tesla-battery-in-south-australia-primed-for-big-upgrade-20191119-p53byo.html
 

Re: Mains frequency

Posted by AncientMariner on Feb 17, 2020 9:03 pm

With my County Councillor hat on.
A couple of weeks ago, I sat through a Council meeting where on page 56 of 216...( http://committeemeetings.flintshire.gov.uk/documents/g4472/Public%20reports%20pack%2028th-Jan-2020%2014.00%20Flintshire%20County%20Council.pdf?T=10&LLL=0 ) I was faced with:-

Solar PV at Flint Landfill and Crumps Yard Connah’s Quay
The Council has been investing in renewable energy systems for many years. Many schools, offices, leisure centres etc. have building scale renewable energy including solar PV, solar thermal, wind and biomass heating systems. The Council has completed the installation of 2 ground mounted solar PV systems on former landfill sites in Buckley, which have a combined output of 1 MW. In order to achieve the goals set within the Carbon Management Plan and the Renewable Energy Action Plan further investment in large scale renewable energy is needed.

This business case is for the development of ground mounted solar PV at Crumps Yard, Connah’s Quay and Flint Landfill. This would potentially generate 3.4MW of electricity per annum. A detailed report explaining the full business case for the scheme was approved by Environment Overview and Scrutiny Committee and Cabinet in December 2019. Construction is due to start in the Spring of 2020.

Direct Costs:
The scheme cost to build, and it is assumed that borrowing will be required to finance the project, is between £2.8m and £3.1m.
Direct Benefits:
Combined net project income over 35 years is estimated to be between £0.750m and £1.25m or between £0.030m and £0.367m in real terms.

Meeting the priorities and objectives set within the Council Plan under the ‘Green Council’ theme
Contributing towards the achievement of Welsh Government targets and obligations under the Climate Change Act, Wellbeing of Future Generations Act and Environment Act.
Future proofing for the requirement to decarbonise by 2030 from Welsh Government
Generated income can also be used to hedge against energy price increases

Indirect Benefits:
Protecting frontline services by providing a long term income stream
Supporting wider regional priorities such as the regional growth bid.
Being a community leader and developing a reputation as a Council who is forward looking, innovative, and invests in the future
Facilitating further innovation around storage technologies, electric vehicle charging etc.
Supporting economic growth and job creation through the initial construction and then the long term maintenance of systems as well as providing the energy infrastructure to sustain businesses and economic growth.
Renewable energy systems are also capital assets which can provide capital receipts on sale/transfer
Developing new ways of working and partnerships e.g. joint ventures, energy service companies.
Improving the ecology and biodiversity of sites following best practice, e.g. wildflower meadows on solar farms etc.

After the presentation, I queried the figures and received this email:-
Dear Councillor Carver
Further to your question at Council on Tuesday, I can now confirm the following.

The estimated annual generation (based on the design calculations) is 3,490,111 kWh or 3.490 MWh. This is the total amount of electricity that is expected to be produced over one calendar year. If you divide this by 365 days then you get a daily output of 9562 kWh, not 10 kWh per day.

I have also include the Cabinet papers from December when the Business Case was approved.  It had previously been endorsed by the Environment Scrutiny Committee earlier in December.

I replied:-


Thank you for your email together with the attached Cabinet papers.

First of all, when I spoke at Council last Tuesday, my comments were based on the figures before me in the Report which on page 56 paragraph 1.37 “This would potentially generate 3.4MW of electricity per annum”.

Regretfully, that sentence is totally incorrect.  I say that simply because referring to MW (Megawatt) is actually referring to Power which is an instantaneous quantity; as in a 100 watt light bulb, or a 2 kilowatt electric heater. What should have been advised in that Report, is the total Energy produced in a year, which for electricity generation is measured in watt-hours (W/h), kilowatt-hours (kW/h, Megawatt-hours (MW/h) or Gigawatt-hours (GW/h) etc.

Reading through the Cabinet papers, the Executive Summary on page 419 only refers to MW as does paragraph 1.01 in “EXPLAINING THE GROUND MOUNTED SOLAR PV AT FLINT LANDFILL AND CRUMPS YARD” on page 420.

Then on page 426 in paragraph 1.12 is the first mention of MWh where it states, “The schemes will produce around 3.5 MWh of renewable electricity every year…..” (MWh and MW/h both being identical.)

And again on page 448 in 3.6 Non-Financial Benefits “The schemes will produce around 3.5 MWh of renewable electricity every year…..”

You can probably now see where I am coming from.

Both the report to Council and to Cabinet have errors of principle, both in the confusion between MW and MWh and also in the numerical figure.

Using the figure as stated in the above reports, 3.5 MWh every year DOES equal 9.59 kWh per day (ie 3,500 kWh divided by 365 equals 9.589 kWh)  My 10 kWh per day was from a back of an envelope calculation based on the figures before me.

However having now read the report to Cabinet, I can see where your figure of 3,490,111 kWh comes from, although this annual figure was not included in the report to Council. However a typo did slip in on your email, since 3,490,111 kWh is 3,490.111 MWh, not 3.490 MWh.

My concern is that most Members and possibly the writer of the reports do not understand the difference between Power and Energy and if the projected income to FCC in the future does not live up to expectations, analyses of Cabinet and Council decisions at that future time would show the confusion in these documents.

Although the Glossary on page 434 has “MW: Mega Watt or 1000 kW (kilo watt)” The list does not include MWh let alone MWp, which is the Peak Instantaneous output power of the system. ie at maximum sunshine.

At least on page 443 where it states, “In 2018-2019 the Council consumed circa 18,641 MWh of electricity (equivalent to the power used in around 5600 homes)…”  I can see some sense in those figures, the daily estimated consumption for each of the 5600 homes being 9.12 kWh, which I will not argue with.

I should add that I have some experience of electricity generation from when I was in the Merchant Navy; for my last 4 years prior to retirement, I was engaged as an electrical and electronics trouble shooter on container ships where electricity generation was often at 6.6 kV obtained from diesel alternators and static inverters, each typically 2.4 MW about 10 MW total.

Kind regards

Guess that's me off a few Christmas Card lists.... 
Clive




 
Clive S Carver GCGI IEng MIET MITP

Re: Mains frequency

Posted by perspicacious on Feb 17, 2020 9:27 pm

Guess that's me off a few Christmas Card lists.... 

Welcome to my world Clive! Well done for the time criticising (sorry, evaluating) their report............... 

I'm corresponding with a place of education offering a 3 year MEng in Engineering in conjunction with industry that is designed to meet the educational requirements of CEng whose prospectus sells it on the basis of no A level Maths or Physics entry requirements, no lectures and no exams............................................ Ramipril here I come!

Regards

BOD 

Re: Mains frequency

Posted by AncientMariner on Feb 17, 2020 10:09 pm

Keep away from Ramipril, you might get rashes and swellings that would do a student proud!
My cardiologist took me through a quantum leap recently.  From  my GP swapping me off Ramipril to something else, then something else and again something else; my cardiologist said STOP and see what happens. My BP has gone a bit higher, and he reckons that if I can lose a "few" kg, then I'll be fine without any BP medication.
Clive 
 
Clive S Carver GCGI IEng MIET MITP

Re: Mains frequency

Posted by Chris Pearson on Feb 17, 2020 10:55 pm

AncientMariner:
Keep away from Ramipril, you might get rashes and swellings that would do a student proud!
My cardiologist took me through a quantum leap recently.  From  my GP swapping me off Ramipril to something else, then something else and again something else; my cardiologist said STOP and see what happens. My BP has gone a bit higher, and he reckons that if I can lose a "few" kg, then I'll be fine without any BP medication.

Would that that were the case. When I got diagnosed with excessive voltage, I lost some weight, but it didn't make an ounce of difference. But you can play with QRisk on line to see how your blood pressure and lipids affect your personal risk assessment.

Re: Mains frequency

Posted by Chris Pearson on Feb 17, 2020 10:57 pm

AncientMariner:
With my County Councillor hat on.
A couple of weeks ago, I sat through a Council meeting where on page 56 of 216...( http://committeemeetings.flintshire.gov.uk/documents/g4472/Public%20reports%20pack%2028th-Jan-2020%2014.00%20Flintshire%20County%20Council.pdf?T=10&LLL=0 ) I was faced with:-

Solar PV at Flint Landfill and Crumps Yard Connah’s Quay
The Council has been investing in renewable energy systems for many years. Many schools, offices, leisure centres etc. have building scale renewable energy including solar PV, solar thermal, wind and biomass heating systems. The Council has completed the installation of 2 ground mounted solar PV systems on former landfill sites in Buckley, which have a combined output of 1 MW. In order to achieve the goals set within the Carbon Management Plan and the Renewable Energy Action Plan further investment in large scale renewable energy is needed.

This business case is for the development of ground mounted solar PV at Crumps Yard, Connah’s Quay and Flint Landfill. This would potentially generate 3.4MW of electricity per annum. A detailed report explaining the full business case for the scheme was approved by Environment Overview and Scrutiny Committee and Cabinet in December 2019. Construction is due to start in the Spring of 2020.

Direct Costs:
The scheme cost to build, and it is assumed that borrowing will be required to finance the project, is between £2.8m and £3.1m.
Direct Benefits:
Combined net project income over 35 years is estimated to be between £0.750m and £1.25m or between £0.030m and £0.367m in real terms.

Meeting the priorities and objectives set within the Council Plan under the ‘Green Council’ theme
Contributing towards the achievement of Welsh Government targets and obligations under the Climate Change Act, Wellbeing of Future Generations Act and Environment Act.
Future proofing for the requirement to decarbonise by 2030 from Welsh Government
Generated income can also be used to hedge against energy price increases

Indirect Benefits:
Protecting frontline services by providing a long term income stream
Supporting wider regional priorities such as the regional growth bid.
Being a community leader and developing a reputation as a Council who is forward looking, innovative, and invests in the future
Facilitating further innovation around storage technologies, electric vehicle charging etc.
Supporting economic growth and job creation through the initial construction and then the long term maintenance of systems as well as providing the energy infrastructure to sustain businesses and economic growth.
Renewable energy systems are also capital assets which can provide capital receipts on sale/transfer
Developing new ways of working and partnerships e.g. joint ventures, energy service companies.
Improving the ecology and biodiversity of sites following best practice, e.g. wildflower meadows on solar farms etc.

After the presentation, I queried the figures and received this email:-
Dear Councillor Carver
Further to your question at Council on Tuesday, I can now confirm the following.

The estimated annual generation (based on the design calculations) is 3,490,111 kWh or 3.490 MWh. This is the total amount of electricity that is expected to be produced over one calendar year. If you divide this by 365 days then you get a daily output of 9562 kWh, not 10 kWh per day.

I have also include the Cabinet papers from December when the Business Case was approved.  It had previously been endorsed by the Environment Scrutiny Committee earlier in December.

I replied:-


Thank you for your email together with the attached Cabinet papers.

First of all, when I spoke at Council last Tuesday, my comments were based on the figures before me in the Report which on page 56 paragraph 1.37 “This would potentially generate 3.4MW of electricity per annum”.

Regretfully, that sentence is totally incorrect.  I say that simply because referring to MW (Megawatt) is actually referring to Power which is an instantaneous quantity; as in a 100 watt light bulb, or a 2 kilowatt electric heater. What should have been advised in that Report, is the total Energy produced in a year, which for electricity generation is measured in watt-hours (W/h), kilowatt-hours (kW/h, Megawatt-hours (MW/h) or Gigawatt-hours (GW/h) etc.

Reading through the Cabinet papers, the Executive Summary on page 419 only refers to MW as does paragraph 1.01 in “EXPLAINING THE GROUND MOUNTED SOLAR PV AT FLINT LANDFILL AND CRUMPS YARD” on page 420.

Then on page 426 in paragraph 1.12 is the first mention of MWh where it states, “The schemes will produce around 3.5 MWh of renewable electricity every year…..” (MWh and MW/h both being identical.)

And again on page 448 in 3.6 Non-Financial Benefits “The schemes will produce around 3.5 MWh of renewable electricity every year…..”

You can probably now see where I am coming from.

Both the report to Council and to Cabinet have errors of principle, both in the confusion between MW and MWh and also in the numerical figure.

Using the figure as stated in the above reports, 3.5 MWh every year DOES equal 9.59 kWh per day (ie 3,500 kWh divided by 365 equals 9.589 kWh)  My 10 kWh per day was from a back of an envelope calculation based on the figures before me.

However having now read the report to Cabinet, I can see where your figure of 3,490,111 kWh comes from, although this annual figure was not included in the report to Council. However a typo did slip in on your email, since 3,490,111 kWh is 3,490.111 MWh, not 3.490 MWh.

My concern is that most Members and possibly the writer of the reports do not understand the difference between Power and Energy and if the projected income to FCC in the future does not live up to expectations, analyses of Cabinet and Council decisions at that future time would show the confusion in these documents.

Although the Glossary on page 434 has “MW: Mega Watt or 1000 kW (kilo watt)” The list does not include MWh let alone MWp, which is the Peak Instantaneous output power of the system. ie at maximum sunshine.

At least on page 443 where it states, “In 2018-2019 the Council consumed circa 18,641 MWh of electricity (equivalent to the power used in around 5600 homes)…”  I can see some sense in those figures, the daily estimated consumption for each of the 5600 homes being 9.12 kWh, which I will not argue with.

I should add that I have some experience of electricity generation from when I was in the Merchant Navy; for my last 4 years prior to retirement, I was engaged as an electrical and electronics trouble shooter on container ships where electricity generation was often at 6.6 kV obtained from diesel alternators and static inverters, each typically 2.4 MW about 10 MW total.

Kind regards

Guess that's me off a few Christmas Card lists.... 
Clive

Legible version!

Re: Mains frequency

Posted by AJJewsbury on Feb 17, 2020 11:09 pm

(MWh and MW/h both being identical.)

Oh dear, I can feel the ghost of my old physics teacher threatening to clip me about the ear for even thinking of uttering such a thing. The words something like  'dimensional homogeneity' drift across the mists of the years (possibly inappropriately). MWh are Mega Watt Hours - the product of power & time -  MW/h would be Mega Watts per Hour -  a rate of power - completely different units (by a factor of 1/hours²).
  - Andy. 
 

Re: Mains frequency

Posted by davezawadi on Feb 18, 2020 8:26 am

Dear me Clive, I hope you are not paying for this. If I were anything to do with a report like this where whoever wrote it doesn't even understand what is being written, and makes claims about output, cost, and repayments which are clearly nonsense, it would be a simple case of "on your bike"! Electricity for 5600 houses? What about when it is dark (when a lot of domestic consumption takes place)? This is a case of "someone else will pay for the gas turbine capacity required, so that you and I can make a few bob". This is entirely the problem with the whole renewables scam, making it work in any useful way is "someone else's problem" while we get a bit of kudos. How much are they expecting to be paid for this electricity? £100 per MWh might well put an entirely different polish on the plan. Flintshire is also a bit far North for effective solar, it does make quite a difference to output and again the payback. On a lighter note the MW/hr when it is dark are negative due to the stuff on standby!
Regards David CEng etc.

Re: Mains frequency

Posted by Kelly Marie on Feb 18, 2020 11:20 am

I'm just waiting for some smart arse to invent moonlar panels ie solar panels that work off moonlight no I don't think that can ever be but it's fun to imagine. Icidentley I've got to go to Southampton hospital tomorrow my heart still isn't right so they want fettle it a bit more I'm scared but what can you do

Re: Mains frequency

Posted by Alasdair Anderson on Feb 18, 2020 1:20 pm

It wouldn't be moonlar panels but lunar panels (think lunacy, lunatic, etc.)
Alasdair

Re: Mains frequency

Posted by mapj1 on Feb 18, 2020 1:36 pm

@ DZ I am to be found more or less equidistant  from Southampton and Winchester most of the year..

Lunar panels as described above do figure in the seminal work Wallace and Gromit: The curse of  the Were Rabbit, Ardmaan 2005 ;
but I do not think that can be cited as a credible technical reference on this matter, on closer inspection there are numerous inconsistencies with the science in the work, not least a dog that drives and understands electronics.

You may be amused to know that real lunar panels have also been proposed.
Article at NASA   The idea is to have solar panels on the moon, and then a directed energy death ray  focused microwave beam to channel the energy back to earth.  
There are some very good reasons this utterly hare brained   scheme has also yet to leave the drawing board.

 
regards Mike

Re: Mains frequency

Posted by Alasdair Anderson on Feb 18, 2020 1:58 pm

mapj1:
@ DZ I am to be found more or less equidistant  from Southampton and Winchester most of the year..

I think you need to be a bit more specific - Aberystwyth is more or less equidistant from Southampton and Winchester. I guess you mean between the two.

I like your comments on the lunar panels, but the installation costs for the moon will be way in excess of the solar ones Clive is commenting on, presumably one of the 'good reasons' it is not off the ground yet - no pun intended.

Alasdair

Re: Mains frequency

Posted by ebee on Feb 18, 2020 2:13 pm

Alasdair Anderson:

mapj1:
@ DZ I am to be found more or less equidistant  from Southampton and Winchester most of the year..

I think you need to be a bit more specific - Aberystwyth is more or less equidistant from Southampton and Winchester. I guess you mean between the two.

I like your comments on the lunar panels, but the installation costs for the moon will be way in excess of the solar ones Clive is commenting on, presumably one of the 'good reasons' it is not off the ground yet - no pun intended.

Alasdair

 

Like it Alisdair , equidistant.
Would you need to drive in a 4` moon rod or would you avoid moonquakes?

Re: Mains frequency

Posted by OMS on Feb 18, 2020 6:59 pm

Kelly Marie:
 Icidentley I've got to go to Southampton hospital tomorrow my heart still isn't right so they want fettle it a bit more I'm scared but what can you do

 
Good luck with it - no point telling you not to worry, you will anyway.
Just keep reminding yourself you will be home for tea and sticky cakes after the MO stops fiddling about - they do know what they are doing, mostly

Take it steady

OMS
 
The trap we've fallen into is to believe that a thousand incompetents properly organized can do the job of a few dozen outstanding people

Re: Mains frequency

Posted by Kelly Marie on Feb 18, 2020 7:11 pm

Hey thanks il look forward to a sticky bun or 3  

Re: Mains frequency

Posted by OMS on Feb 18, 2020 7:19 pm

Kelly Marie:
Hey thanks il look forward to a sticky bun or 3  

 
Stick to two - save one for the next day - always 👍

OMS 
The trap we've fallen into is to believe that a thousand incompetents properly organized can do the job of a few dozen outstanding people

Re: Mains frequency

Posted by Chris Pearson on Feb 18, 2020 11:41 pm

mapj1:
@ DZ I am to be found more or less equidistant  from Southampton and Winchester most of the year...

That's too easy - does it begin with a P or a W? 😉

Re: Mains frequency

Posted by mapj1 on Feb 18, 2020 11:55 pm

No. think private sector, not MOD, and I did meant near equidistant, not "midway", but to limit the circles of confusion,  I do meet a few brave folk at work who cycle in from each of those cities. And others, like me who drive in from not so far away as either. I'm not keen to reveal much more detail on an open forum. Those who need to find me, can.

 
regards Mike

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