UK's first full day without coal generating electricity.

[APOLLO]

Interestingly I saw this on realtime trains

 

618P 0535 Ferrybridge C Pwr Stn Flhh to Fiddlers Ferry P Stn Flhh  

 

 

http://www.realtimetrains.co.uk/train/R01269/2017/04/26/advanced

 

Runs 24 - 28 April SSu excepted. 2200 Tons. So I presume taking coal from stock at Ferrybridge C to Fiddlers Ferry, which I thought had closed for good.

 

Coal east west across the pennines and biomass back the other way - I wonder which way the electricity flows through the "new" Woodhead tunnel !!

 

Brit15

[peach james]

 

 

None of the above relates to carbon emissions. In terms of carbon, I’m not a carbon modeller but one thing that did always strike me was that in large plants biomass is a long run for a short slide. The low CV means you need a lot of fuel and boilers are huge for the power output. I worked at the construction and the commissioning of what was at the time the UK’s largest dedicated biomass plant. The turbine output was 51MW and the boiler was rated at just over 150MW if I remember rightly with a plant design efficiency of 35%. So that basically means that for every three trees you threw in the boiler you were throwing two of them away (in fairness a modern supercritical coal plant will struggle to go above 45%). Those figures aren’t great, however the plant had a parasitic load of 8MW, so getting on for 16% of plant output was needed just to make the plant work. Which is why I referred to the low parasitic load of a dry emissions plant as being highly advantageous. The efficiency of 35% does not include this parasitic load, it is rankine cycle efficiency and purely based on the thermodynamic cycle, so the true efficiency in terms of energy in, useful energy to grid is much lower (there will be various other losses such as electrical losses too). The nature of the fuel imposes a huge load to power conveyors, drag links, screw reclaimers etc as well as FD and ID fans, feed pumps etc.

 

 

 

 

Glup.

 

OK, so oil fired steam at sea.  We fired 7050 lb/hr x2 into the boilers at full power.  (That's F-76, or MGO, depending on who you are...), post conversion.  The rated plant output was 21 000 shaft HP, plus 2 MW(e) at that.  We could make fairly close to that HP while generating 1.5 MW(e) and dumping ~10 000 lb/hr of saturated steam into the evaporators.  Overall plant n of about 33%, from a mobile plant.  Parasitic losses:  Well, we were running steam feed pumps (Cofflin CG's, same as on Red Devil) which were rated at 6000 lb/hr of steam in the setup we were using.   Meaning that desup steam was about 18000 lb/hr, and rated was 176 000 lb/hr of s/h steam.  Fuel flow was the only real measured value, as steam flow was set based on one boiler operation at max fuel flow.  At any rate, we could get steam up with 500 kw, and the total plant load was under 1 MW(e), for electric forced draft fans, electric fuel oil pump, steam lube oil pump, electric hotwell (extraction) pump, electric feed boost pump, electric feed transfer pump.  Everything should have been able to be single except the fd fans, which were usually operated as a pair, and there was no real savings singling them.  (you ran out of air before fuel, making your own cloud to hide your shame in).  Parasitic losses of 8 MW...my mind boggles...I don't doubt it, but it still boggles.

 

jjb, I don't doubt the boilers were rated as 150 MW, but that would likely be MW(t), which is a basically useless number from the real world side.  The n of the boilers would probably be somewhere around 85% at rated (probably a bit higher, possibly as high as 92 or 93), but I would suspect that the "nameplate" was how much heat was going into them.  I'd also suspect, that if the plant n was as low as 35%, that it was a subcritical plant, and that the cooling was being provided by air based exchangers.  (which would add to the losses...)  Even sailing in the IO and PG, with seawater temps of 96F or hotter, we still could pull down to 28.3" or better for vacuum, which is really quite important for n.   

 

I would have expected better performance from a fixed installation, and especially from a "green" powerplant.  Someone, somewhere, was fiddling the $ to get this dog off the ground.  16% parasitic losses, 35% fuel:hydro, meaning an actual n of 28%.  All of a sudden, Buster Keaton seems to be more environmentally friendly than I thought !

 

 

James Powell, BC 3rd Class Power Engineer (& tanker EOOW)

[jjb1970]

High parasitic loads are a characteristic of biomass due to the nature of the fuel. The low CV means you burn a lot of it, and it is transferred using a series of large reclaimers, drag links and conveyors which need a lot of power, way more than the power needed to get liquid fuel to the boiler or engine. Then you have the normal steam plant loads like feed pumps, FD fans, ID fans, the EGR fan etc which are pretty big loads. That said there is no doubt that a 16% parasitic load is very high and a bit bonkers (although that is nothing compared to some of the CCS technologies trialled or proposed which can be a third of plant output).

The low thermal efficiency was a mix of the nature of the fuel and emissions control. The plant was sub-critical. MWt is a standard way of rating equipment in the electricity generating sector, particularly where heat is a commodity (customers are metered and invoiced based on MWth). Even modern supercritical coal plants aren't that efficient, they struggle to go above 45% and that requires heavy use of nickel based super alloys to handle the high temperatures. Using EGR and the fuel/air curves to suppress NOx is effective but carries an efficiency penalty, that however was more advantageous than injecting urea to abate NOx with SNCR let alone fitting an SCR in terms of cost. The best way to boost efficiency is to tie the power plant into a CHP scheme and a lot of the CCGT plants do operate as CHPs and achieve extremely impressive thermal efficiencies, the problem for that is finding somebody wanting enough heat to get a decent heat balance in a large steam plant.

Conventional steam plants just aren't very efficient. Most power companies went over to CCGT plants because they're a lot cheaper to build, low maintenance, clean and can be staggeringly efficient even without the benefit of CHP. Biomass only really makes sense because of the subsidy regime, the biomass plant I was a part of would never have been built if it wasn't for the subsidies as it was a financial basket case without the subsidies. Coal can make a lot more financial sense, but it's still not particularly efficient and lags way behind CCGTs and internal combustion engine plants which can achieve efficiencies well in excess of 80%.

[PatB]

Whilst I'm generally in favour of burning biomass (though I don't have the technical knowledge of the subject that other posters here demonstrate) I do recognise that it's only going to make real sense in areas where there is a local source of fuel in sufficient quantity and of sufficiently low cost (preferably a waste product)  to feed a decent sized plant. Areas with a high level of forestry activity, or reliable large quantities of seasonal harvest waste perhaps. Mind you, I don't know how many areas of the world might have such a fuel source.

 

As for handling and storage, liquid or gaseous fuels will certainly beat it in terms of energy requirements and storage. I'm less sure about coal though. I've done some engineering work on coal stockpile and reclaim areas and, even with fossil fuel energy densities, the stacking and reclaiming gear is substantial. I was also led to believe that coal stockpiles, too, are subject to spontaneous combustion if left undisturbed for more than a fairly short period of time. Certainly the ones I was involved with became rather warm inside after only a few days. Whilst I can see that biomass would need to be handled in greater bulk, and so equipment would need to be commensurately physically larger, from memory, in material handling work, energy requirements are roughly proportional to mass flow rather than volume flow, and so the increase needn't be as bad as might at first appear. That's based on hazy memories and assumptions rather than recent personal experience though, so I'm finding this thread quite educational on the subject.

[jjb1970]

An interesting article in a mailshot I recieve today:

 

http://www.eco-business.com/news/renewable-energy-faces-growing-human-rights-concerns/?utm_medium=email&utm_campaign=May%203%20newsletter&utm_content=May%203%20newsletter+Version+A+CID_62a0db133a8f154982d857718fec2773&utm_source=Campaign%20Monitor

 

This was always going to happen as the renewables sector matured. I'm always a bit sceptical about some of this stuff. I've no doubt a lot of it is true, I also think that based on my experience in O&G and electricity generation that big energy companies attract these stories and in many cases things are not as presented in reports such as this.

[PatB]

An interesting article in a mailshot I recieve today:

 

http://www.eco-business.com/news/renewable-energy-faces-growing-human-rights-concerns/?utm_medium=email&utm_campaign=May%203%20newsletter&utm_content=May%203%20newsletter+Version+A+CID_62a0db133a8f154982d857718fec2773&utm_source=Campaign%20Monitor

 

This was always going to happen as the renewables sector matured. I'm always a bit sceptical about some of this stuff. I've no doubt a lot of it is true, I also think that based on my experience in O&G and electricity generation that big energy companies attract these stories and in many cases things are not as presented in reports such as this.

Whilst the article may have distortion in the detail, I would accept that it is likely that for-profit companies operating in a loosely regulated or effectively unregulated environment will, on occasion, be guilty of ethically reprehensible conduct and I'm not sufficiently starry eyed about renewables to believe that businesses and governments operating in the sector are somehow different. I would, however, regard it not as a problem with renewables per se, but one with the business and legislative environment which allows it to happen. That it may be currently a particular concern within the renewables sector is likely a result of  the huge expansion the sector is currently undergoing rather than any particular feature of renewable energy itself.

 

In other words, yes it's probably a valid concern but it would be unfair to use it as a stick to beat the concept of renewables.

[jjb1970]

Whilst the article may have distortion in the detail, I would accept that it is likely that for-profit companies operating in a loosely regulated or effectively unregulated environment will, on occasion, be guilty of ethically reprehensible conduct and I'm not sufficiently starry eyed about renewables to believe that businesses and governments operating in the sector are somehow different. I would, however, regard it not as a problem with renewables per se, but one with the business and legislative environment which allows it to happen. That it may be currently a particular concern within the renewables sector is likely a result of  the huge expansion the sector is currently undergoing rather than any particular feature of renewable energy itself.

 

In other words, yes it's probably a valid concern but it would be unfair to use it as a stick to beat the concept of renewables.

 

I agree. Electricity companies are profit making entities in it for the financial return. I found with O&G and electricity companies that they generally behave much better than given credit for but I saw enough in certain countries to be under no illusions as to the less salubrious side of things.

[Horsetan]

...The greens just don't understand base load. Freezing cold winters night, still ail = no wind, no solar. 5.00pm, peak energy use, heating on, cooking on TV on etc ....

Or perhaps they don't want to because it doesn't fit their agenda.

[30801]

Seems like Germany had a windy yet sunny weekend.

 

https://www.digitaltrends.com/cool-tech/germany-renewable-energy-85-percent/

[QWILPEN]

A record amount of solar power was generated on Friday as Britain basked in sunshine and temperatures of up to 28C, the National Grid has said.

It said 8.7 gigawatts (GW) had been generated at lunchtime, representing 24.3% of total generation across the UK.

 

http://www.bbc.co.uk/news/business-40058074

[Ozexpatriate]

It said 8.7 gigawatts (GW) had been generated at lunchtime, 

More than enough for seven flux capacitors.

[APOLLO]

Renewables provide more than half UK electricity for first time

 

National Grid reported that, on Wednesday lunchtime, power from wind, solar, hydro and wood pellet burning supplied 50.7% of UK energy. Add in nuclear, and by 2pm low carbon sources were producing 72.1% of electricity in the UK.

Wednesday lunchtime was perfect for renewables - sunny and windy at the same time. Records for wind power are being set across Northern Europe.

 

http://www.bbc.co.uk...siness-40198567

 

Brit15

[billbedford]

Perhaps people need reminding of the consequences of of the increase in renewables in terms of the effect on their electricity bills.....

[The Stationmaster]

Perhaps people need reminding of the consequences of of the increase in renewables in terms of the effect on their electricity bills.....

 

Actually it has a nice effect on my energy bill as the more solar power I generate so the more money I am paid.  But yesterday would no doubt be a better overall comparison as it was cloudy and therefore solar output was reduced.

[jjb1970]

The cost of renewables has to be considered in the context of the costs of not doing something to mitigate climate change. There is a cost to reduce carbon emissions but the cost of not doing so is generally agreed to be high. Coal has a particularly high carbon footprint and the costs of carbon capture and sequestration are not cheap (assuming you find an effective and reliable way of doing it). Personally I find much to criticise in the way governments incentivised renewables and do believe that many renewable projects were more subsidy generator than electricity generator. That is not however an argument against the shift to renewables, it is an argument about implementation and government policy. I’m not really a supporter of government interference in things but do accept that government incentives (or punitive measures) have a place in environmental protection, but measures need to offer good value. Given that it is generally agreed that there are issues with intermittency of some renewable technologies it would have made more sense to invest in energy storage alongside generation (eg. Battery storage, hydrogen production etc). There is also the issue that fossil fuels are a finite resource and it would not take that much of a growth in demand for oil supplies in particular to become much tighter. Oil isn’t coal, but a big spike in oil prices would probably be much more costly to consumers than the cost of subsidising renewables. Not to mention the public health benefits offered by battery and fuel cell powered vehicles.

[Zomboid]

Perhaps people need reminding of the consequences of of the increase in renewables in terms of the effect on their electricity bills.....

And on the other hand the consequences of burning fossil fuels in terms of 1. Having any left in a few decades and 2. The continued ability of our planet to support human existence.