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Comment Re: I guess they didn't get the memo... (Score 4, Interesting) 79

The UK is part of the European Grid already. There is a 1000MW pair of interconnectors between the UK and Ireland about 3000MW interconnector between France and the UK. The direction of flow depends on the price and the amount of Wind makes quite a big difference.
I don't know how the figures for the UK (their Electricity demands are at least 10x that of Ireland) but i can tell you that the maximum amount of renewable energy allowed on the grid is around 75%

The daily cycle for Ireland runs between 3000MW off peak to 6000MW at peak. The current record for wind generation in Ireland is about 4,500 MW.

So that 4,500 figure would have been produced around the time of Peak demand (about 75%) Perhaps more interesting is when there is high Wind and low demand. When demand is low about 3000MW there is at least 4,500 MW of potential Wind generation available. it depends on weather and time of year. It can be as low as 100MW. more typical would be above 1000MW.

Anyway lets take a scenario where its the middle of the night demand is around 3000MW and there is an excess of Wind in Ireland . As you need grid stability you are limited to around 75% wind so around 2250MW but you have the interconnectors which can take around 1000MW so if the price is right which it usually is with wind Ireland would be exporting so now the demand is 4000MW and now you can use 3000 MW of wind and 1000MW of that goes to the UK. If there is less wind available than upto a 1000MW flows into Ireland. So you could have a situation where 60 percent of generation is from Irish Wind farms and most of the rest is via the inter connectors between UK and Ireland.

It's also worth bearing in mind that fuel for conventional generation is mostly imported so using Wind when its available is a good thing. Ireland also has battery sites as well which can dump a lot of Electricity onto the grid in a fraction of a second and then maintain that output if needed for 2 or 3 hours, This covers the period needed to bring up more conventional generation.

The future is quite interesting, there is already ongoing construction of an interconnector between Ireland and Spain (which is a great location for Solar) There are a couple of interesting projects for storage.

In Berlin at one generating station they are building a large water tank which is mainly for district heating but is going to hold water at up to 90 degrees C (about 200 MW) it's intended that excess Wind generation will be used to generate the heat. However conventional generation needs to raise steam to run and if the water is at 90 degrees to start with rather than say 10 degrees. You don't need to burn so much fuel. The article I read said they can keep it hot for around 13 hours. Which would help shift wind generated power generated off peak to on peak. The German site looks to be ready for September just a few months really for the construction.

There is also another project I read about where the idea was to heat sand to 500 degrees C. Electric Cars are going to need charging and the time to do so is overnight when demand is low. We already have plenty of capacity since we have to be able to generate enough for peak times.

At the very least realise that national grids do not work in isolation and Electricity can be supplied where its needed. You still need infrastructure in place, and some of it needs to be beefed up to carry higher capacity loads. Even Brexit hasn't changed things much if it all about Electricity generation. In Ireland we have 2 countries but one grid sometimes control is in Dublin and at others it's in Belfast.

Electricity is Electricity, how it's generated is not a simple black and white issue.
                     

Comment Re:Marginal benefit (Score 1) 127

If you read the article you will see that it's being built on the site of an existing power station. A conventional generator starts by making steam from heating water. If the water is hot already it means less fuel needs to be burned to generate that steam, if that is normally generated by gas, you will burn a lot less gas.

The other thing that you need to look at is the daily cycle of power usage. At night its around half that of the peak, this tends to coincide with higher wind levels in general. Wind generation is generally higher in the winter too.

Another factor is grid stability, I can't say for Germany but here in Ireland around 75% is the maximum of renewable energy that is currently allowed on the grid. To give some context in Ireland peak demand is around 6000MW maximum wind used currently stands around 4,500 MW night time demand is around 3000MW. I can't say what the installed wind generation is but it's over 4,500 MW. Ireland has 2 interconnectors between Ireland and the UK with a capacity of 1000MW.

OK so the most amount of wind power that can be put on the grid is 75% of demand so as it happens 4500 is about 75% of peak demand 6000 MW now off peak being half that your maximum at 3000MW demand is 2,250 MW roughly. The interconnectors can boost demand by exporting to the UK another 1000MW but thats still around 3000MW of wind energy that can be used. There is still another 1,500 MW plus that can't be used if there is enough Wind energy available. So currently this has to be curtailed.

Now Germanys hot water tank is essentially a buffer. This helps balance the grid by helping to match supply with demand if there is more Wind than expected it takes in more energy and if the wind drops it takes in less and when there is available capacity on the grid it can give it back to the grid. It's kind of a massive smoothing capacitor. Incidentally a typical gas fired generator is around 400MW output.

Power generation is planned with 4 auctions a day and Wind forecasts are done hourly, obviously the Forecast for the next hour is a lot more accurate than the one for 24 hours time but each forecast goes out to around a week anyway. The price is set for the hour by the bids into the market the more generation capacity there is compared to demand the lower the cost for that hour. At peak demand the available supply can get pretty low and the price per megawatt can go through the roof. If there is enough wind generation the most expensive peaking plants will not need to be turned on and the cost is much lower.

A relatively small reduction in peak demand would have a large impact in the retail market.
your typical electricity retailer is selling at a profit most of the day between 5 and 7pm or 4-8pm they sell at a loss. So the day rate is set higher to cover the loss. recent times have caused the peak price to be higher and business plans to be destroyed as the amount built into the day rate.
                               

Comment Re:This is still one step behind the times. (Score 1) 230

It's a bit more than that, having a port is a failure point, have you never had a port become loose or even detach from the board. It is pretty handy having wireless chargers e.g on a desk no wires needed to be dug out of a bag and untangled. lets say its a 5,000 maH battery to charge thats 25 watt/hours and a third is about 8 watt's. I think boiling a litre of water takes about 150 watt hours if its efficient and it usually isn't. practically speaking you would waste 2 or 3 KW of electricity a year charging daily. A typical electric shower uses 8.5 KW an hour or about 140 watts a minute which would you could save 8 watts by ending your shower 10 seconds sooner.

Comment Re:Big problem (Score 1) 230

I'd agree with robustness to be fair and apple make some pretty bad devices. e.g they made a lightning charging stand with headset jack and basically balanced the phone on the lightning Port! and i don't think they have made any other splitter than that one. They don't seem to want to make lightning extension cables or right angled connectors. (handy on a gimbal).

Some of the third party hardware developers are pretty bad and well known :(

     

Comment Re:Big problem (Score 3, Interesting) 230

Lightning was introduced 2012 usb-c in 2014.
Apple doesn't get royalties on every lightning cable sold , they do on MFI certified cables that use the official chips and not the chinese knockoffs that just fake the handshake.
The royalties on mfi certified is around $5 though, so if you are paying less it obviously isn't certified.

What assurance do you have on a USB-C cable as to it being a good one or a poorly made one?

Comment Re:Nice to know (Score 2) 80

Well if the solar went to storage and was discharged at night maybe. But since the grid is mixed it's more like a loan the price of electricity is high during the day and cheap at night since the demand is lower, when the cheaper producers can take the load, this might include hydro bio gas and wind. doesn't matter really as long as the solar producer is a net exporter of energy.

Comment Re:BIZX being paid to push the Jew York Slimes (Score 0) 219

To make a difference cut your electricity usage between 5 and 7pm or whenever your countries peak times are.

Basically every hour the grid looks for supply to match demand naturally the cheapest generators get turned on first but they don't get that bid price they get the price per megawatt needed to secure the supply for that hour so with low demand you get a lower wholesale price. During the peak 2 hours price is much higher in fact the price for those 2 hours of the day is around the cost of 10 hours at a lower demand. It can be worse when there are failed generators and its getting close to not being able to meet demand.

Ok so what happens if you reduce demand in the peak hours? well that means less peaking plants get turned on which means the wholesale price is lower. Because those 2 hours are cheaper it means your supplier who buys from the grid can afford to sell Electricity to you at a lower price and less of Putins gas is needed and the price he gets for it is lower.

It doesn't even need to be a huge reduction even 10% less use at peak time would make a pretty big dent in the cost of those 2 hours. This is why there are moves to introduce a peak tariff and charge people a lot more for these 2 hours. That's the stick to beat you with but we could switch our usage today or tomorrow without that stick and see lower prices as a result.

To be fair I don't know how to get this widely known and besides if the two hours cost the same at retail who is going to modify their behaviour? It's a bit hard to wrap your head round the concept that you can lower or minimise the rise in your electricity bill if enough people do this. So I guess peak band pricing needs to come in as soon as possible to modify people's behaviour.

Comment Re:Study by "SuperNode"... (Score 1) 219

The national grids are already connected via interconnectors we do need more of them. In Ireland we tend to use around 6000MW at peak and 3000 MW off peak. We have interconnectors which add up to 1000MW and work both ways. When we have excess Wind Energy it effectively expands demand and allows more Wind energy on the grid, wind is variable but reasonably predictable. There is a series of auctions taking place at 24 hour 12hours and 6 hours in the day. The latest forecasts are made about an hour before the auction takes place. So forecasts are continually updated and are pretty accurate.

The main problem really is the variability in supply you need conventional generation to cover the times when Wind is low and this means there are generators being paid not to produce.

The UK has about 3000MW of interconnector with France and you do get situations where the uk is importing from france at the same time as exporting to Ireland it mostly works ok and the main time there are issues is usually when a large generator trips out say something around 400MW and there is then a scramble to maintain grid frequency until other plants can spin up to replace the lost generation.

As I said at the beginning load varies between around 3000-6000MW on a typical day so mostly there are plenty of generators that can turn on. The dodgy time is between 4 to 8pm which is peak demand and we have had pressure from Covid travel restrictions which has caused maintenance issues and more frequent tripping of power plants. We have coped pretty well to be fair. While low wind days do mean that more gas gets used that is planned for. It would be better to get some more offshore wind commissioned so the minimum wind improves I have seen times where Wind has provided as little as 200MW to around 4,800 MW I know we will be getting more interconnection which will reduce Irelands need for conventional generation.

If you want to be greener just try to reduce your energy usage away from 4 to 8pm. Soon enough the smart metering will allow for demand pricing and you can get some control of how much you are paying out. At least now we should see less extra standing charges which was often doubled if you were using economy 7 with 2 meters which switched over when the bands changed.

Comment Re:Can someone explain (Score 1) 128

Well looking through a lens is something a photographer does more off than taking a photo and to have the actual photons reaching your eyes can be a good thing and that doesn't need any electricity unless you are using an auto focus.

Is there a difference between looking through a window vs looking at a screen? The screen is also going scanline by scan line so what you see at the top of the frame is from a different time from the bottom.

Taking a photograph is easy , taking a good or excellent photo tends to be much harder, spray and pray isn't how to get results. There is definately a difference it's maybe as different as being with an actual woman and watching one on redtube ...

Comment Re:Stop the doublespeak. (Score 2) 328

I know a 60 year old woman with diabetes who was vaccinated and beat covid although she was very sick..

I also know two unvaccinated brothers the older around 40 got Covid and was very sick and told his younger brother he should really reconsider getting the vaccine. Well Covid killed him a couple of days ago, he didn't get vaccinated.

Most people I know have had very little reaction to the pfizer vaccine, I do know a couple of friends who were feeling sick with the vaccine for a couple of days.

It looks like this article is suggesting that a lot of poorer countries will have higher death rates than the "west" Maybe it has been engineered that way to fight climate change, who knows.

regardless it seems taking an mRNA vaccine will largely ensure you get through this, it's an opportunity that millions , billions even do not have.
 

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