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May 20, 2021updated 19 May 2021 5:47pm

The new highs and lows in power transmission, with National Grid ESO 

As renewables cause new highs and lows for energy system operators, how have balancers tackled the changing profile of power?

By Matt Farmer

< b >< span data contrast =” auto “> Every power savvy consumer knows : r span > b >< b >< span data contrast =” auto “> un your electricals in the middle of the night . Specialist tariffs have trained consumers to use electricity in the hours of low demand , traditionally between midnight and dawn . But as the energy transition progresses , these low power hours have crept away from their usual homes . How have transmission system operators fought these Sunday afternoon blues ? span > b >

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Delve into the renewable energy prospects for Morocco

In its new low greenhouse gas (GHG) emission strategy to 2050, submitted to the United Nations (UN), the Ministry of Energy Transition and Sustainable Development (MEM) of Morocco suggested to raise the share of renewable capacity in the country’s total power installed capacity mix to 80%.   Morocco currently aims to increase the share of renewables in total power capacity to 52% by 2030. The new strategy plans to increase the share of renewable capacity to 70% by 2040 and 80% by 2050.  GlobalData’s expert analysis delves into the current state and potential growth of the renewable energy market in Morocco. We cover: 
  • The 2020 target compared to what was achieved 
  • The 2030 target and current progress 
  • Energy strategy to 2050 
  • Green hydrogen 
  • Predictions for the way forward  
Download the full report to align your strategies for success and get ahead of the competition.   
by GlobalData
Enter your details here to receive your free Report.

< span data contrast =” auto “> In 2020 power demand fell   to   all span >< span data contrast =” auto “>- span >< span data contrast =” auto “> time lows . As the pandemic spread across developed nations electricity transmission systems operators   saw   record breaking low days On the island of Great Britain , transmission system operator   National Grid ESO   saw   consumer   power demand   fall to 13 . 4GW   on   28 June , at 5 : 30am This  ‘ trough ’  was a new low for consumer demand 2 . 4GW below   the   pre 2020   record . span >

< span data contrast =” auto “> If   any time could   set a new   low for consumer demand the crack of dawn on a warm summer morning during a pandemic   would be the time network operators expect At the time National Grid ESO   used   pumped hydropower storage   and exports via international interconnectors   to increase   the   network s   load . span >

[ caption id =” attachment_134385 align =” aligncenter width =” 620 “]< img class =” wp image 134385 src =” https :// www . power technology . com / wp content / uploads / sites / 7 / 2021 / 05 / 41343452181_541e3e2991_k 450×340 . jpg alt =” Pumped hydro station near Moelwyn Mawr , Wales .” width =” 620 height =” 349 ” /> Pumped hydro stations provide energy demand when it is needed , but cannot answer all calls . Credit : Andrew / Flickr under CC BY 2 . 0 .[/ caption ]

< span data contrast =” auto “> This extra   demand   prevented   the   night of low customer demand   from being   the   grid s   lowest point over the summer That came   on a bank holiday in May but   unusually it came at three o clock in the afternoon . span >

< span data contrast =” auto “> This time   marked one of the lowest   power   draws in the country s modern history Over 2020 , National Grid ESO   span >noted several occasions< span data contrast =” auto “>  where   the transmission system saw its lowest demand in the early afternoon We spoke to   Julian Leslie , head of networks , to ask how the company addresses the changing face of power . span >

How renewable generation changes transmission network operations

< span data contrast =” auto “> Leslie explained : “ Over the last five or six years we ve seen   much more embedded   renewable   generation connecting to the distribution system  [ outside of the high voltage transmission system ].  This comes   either as large   solar   fields or as domestic solar on people s roofs . span >

< span data contrast =” auto “>“ The phenomena we re seeing now is that , on a Sunday afternoon , there is so much embedded generation that , from our perspective , it effectively offsets consumer demand . That makes the transmission system demand lower at around 2 or 3 o clock on a Sunday afternoon [ than overnight ]. It s a real shift , just because at five o clock on a Sunday morning , there isn t the same amount of solar generation that there is at three o clock on a Sunday afternoon . span >

< span data contrast =” auto “>“ We saw it in 2019 , but we saw it more often in 2020 because overall demand was suppressed   by   Covid 19 . At the minute , it span >< span data contrast =” auto “>’ span >< span data contrast =” auto “> s sort of 3 span >< span data contrast =” auto “>% span >< span data contrast =” auto “>- 4 % below what we would have forecasted   it   to   normally be . As we come into this summer , we re expecting demand to return to roughly where it would have been before Covid 19 . span >

< span data contrast =” auto “>“ But in the meantime , there s two years ’  more solar PV   installed   on people s   roo span >< span data contrast =” auto “> f span >< span data contrast =” auto “> s , and a few more built in the farmer s fields . All of that works towards   counterbalancing   the   transmission   demand we see on   a   Sunday afternoon .” span >

What can transmission system operators do to avoid low power?

< span data contrast =” auto “> Just as happened during the consumer demand trough in June , network operators   can   work with the industry to create extra demand In that case , pumped   hydropower reserves and pre arranged   international exports created 3 . 8GW of extra transmission demand This represents   more than 10 % of average   daily demand for the country , and so dramatically alters the   power dynamics of the system . span >

[ caption id =” attachment_134381 align =” aligncenter width =” 620 “]< img class =” wp image 134381 src =” https :// www . power technology . com / wp content / uploads / sites / 7 / 2021 / 05 / CreditNationalGrid Interconnector IFA2 PR High Res min 450×340 . jpg alt =” IFA2 interconnector transformers width =” 620 height =” 413 ” /> The landing site of the IFA2 interconnector , linking Britain and France . Credit : National Grid .[/ caption ]

< span data contrast =” auto “> However , pumped hydropower cannot act as an infinite reservoir of power . If pumped hydro operators fill their reserves in the afternoon , stations cannot turn on again late at night , when energy prices could have fallen further . For this reason , operators and grid balancers have remained wary of using pumped hydro during afternoon lulls . span >

< span data contrast =” auto “> Leslie elaborated : “ We can instruct pumps to pump , but it makes sense for them to do that anyway , because of low energy prices . We have many more storage batteries to take advantage of that , and on the spot tariffs are a great example of consumers getting the benefit . span >

< span data contrast =” auto “>“ span >< span data contrast =” auto “> Other than that , we need to make sure that we ve got the right balance of energy on the system , so that we have the tools and the flexibility that we need , if we were at a very low point , to  [ be ready to lose a whole bunch of demand or our bunch of generation . span >

< span data contrast =” auto “>“ That becomes quite challenging at low demand levels , but we ve got the tools , we ve got the processes in place , and we demonstrated through last summer that they work effectively .” span >

“How do you meet the nation’s power demands with little wind or sun?”

< span data contrast =” auto “> Last summer , National Grid ESO implemented a   market system allowing to pay suppliers   span >< i >< span data contrast =” auto “> not span > i >< span data contrast =” auto “>  to generate This   Optional   Downward   Flexibility   Market   enabled balancers to suppress power supply just as Covid 19 suppressed demand Some interested parties have said   span >< span data contrast =” auto “> that   span >< span data contrast =” auto “> this system   is   span >‘not sustainable’< span data contrast =” auto “>, but   it demonstrated   the role of   communication in future balancing . span >

[ caption id =” attachment_105075 align =” aligncenter width =” 620 “]< img class =” wp image 105075 src =” https :// www . power technology . com / wp content / uploads / sites / 7 / 2019 / 10 / About_us_Sub_page_Green_energy_is_now_cheaper_than_black_Top_hero 450×340 . png alt =”” width =” 620 height =” 349 ” /> The UK uses some of the world s largest offshore wind fields , such as Hornsea One , off the English coast . Source : Ø rsted .[/ caption ]

< span data contrast =” auto “> Similar systems have become part of the ESO’s five-point plan to manage congestion on the transmission system span >< span data contrast =” auto “> I span >< span data contrast =” auto “> n the future span >< span data contrast =” auto “>  however span >< span data contrast =” auto “>, the balancers hope to control power demand , not just power supply . Leslie said : “ If people were able to control their demand and bring demand on , as opposed to us constraining off wind and solar , then obviously that would be part of that market . span >

< span data contrast =” auto “>“ We see that very much as part of the future we are working on as part of this five point plan . One point looks at a regional flexibility market , which would reward and encourage   span >< span data contrast =” auto “> controllable demands with a better market . If you ve got a large industrial process or a fleet of batteries this   would be   a mechanism for   you   to get engaged with us . span >

< span data contrast =” auto “>“ That system can work within the day , just like pumped hydro . The gap at the moment is really long term storage , for when you get two or three weeks of no wind and little sun . How do you meet the nation s demands at that point ?” span >

Grid-scale power storage “offers alternative to transmission system investment”

< span data contrast =” auto “> Equinor and SSE recently announced their intentions to develop a hydrogen fired plant in the UK , which would   tie into the devolved Scottish Parliament s   intentions to explore hydrogen generation . Leslie said   span >< span data contrast =” auto “> that   span >< span data contrast =” auto “> energy storage in Scotland could prove key , as the country s large renewable generation   gives it great opportunity for grid scale   battery farms . span >

< span data contrast =” auto “> On a wider level , he said : “ I think there will be grid scale storage locally I think the distribution network operators , with their flexibility markets , will be looking to storage as an alternative to regional or local network investment . span >< span data ccp props =”{& quot ; 201341983 & quot ;: 0 ,& quot ; 335559739 & quot ;: 160 ,& quot ; 335559740 & quot ;: 259 }”>  span >

< span data contrast =” auto “>“ In the same way we are looking to transmission grid scale storage with a two to four week duration as an alternative , maybe , to transmission network investment . We need a whole range of different storage solutions , both locally and nationally , at the transmission level .” span >

< span data contrast =” auto “> In the long   term , grid balancers put their faith in on the spot power   domestic   tariffs to change consumer prices based on supply . These would offer preferential rates to consumers using   power during transmission grid troughs . At the same time , these would increase bills for those using power at peak hours . span >

< span data contrast =” auto “> The British energy network has started changing its network infrastructure to allow these tariffs to become more widespread and faster to act . Despite widespread use of digital energy meters , few on the spot domestic consumer tariffs currently exist . span >

[ caption id =” attachment_134384 align =” aligncenter width =” 620 “]< img class =” wp image 134384 src =” https :// www . power technology . com / wp content / uploads / sites / 7 / 2021 / 05 / 5125852229_a9e4be946b_k 450×340 . jpg alt =” Smart meter width =” 620 height =” 428 ” /> ‘ Smart digital meters allow domestic consumers to track and optimise their energy use . Credit : Edinburgh Greens under CC BY 2 . 0 .[/ caption ]

< span data contrast =” auto “> Those   currently available   advertise that during   periods of high supply negative pricing allows   consumers to earn money by using electricity This has remained relatively rare , but as the share of renewables used for generation increases , should consumers expect more negative pricing ? span >

Should UK power consumers expect more negative prices? 

< span data contrast =” auto “> Leslie answered : “ There s more and more wind being built every week . Overall demand across the year is rising , but peak demand isn t , and therefore we will get more periods with more wind than the market needs . span >

< span data contrast =” auto “>” Because of the subsidy regime that we have , wind farms get paid when their blades are turning , so they just want to operate . They ll put in negative pricing into the market , which will ultimately drive behaviours span >< span data contrast =” auto “> that span >< span data contrast =” auto “> will balance span >< span data contrast =” auto “> the market span >< span data contrast =” auto “>  out . span >

< span data contrast =” auto “>“ Smart metering and a half hourly tariff is absolutely a key enabler . I think the consumers are going to want to understand what what s in it for them , and what s the benefit for them to switch . In the home , they ve been enabled by smart devices . span >

< span data contrast =” auto “>“ I can press the button on the dishwasher , and it knows that I just need to have clean dishes in the next 10 hours . It works out when in the next 10 hours is the optimum time to start , either from a cost perspective or a carbon intensity perspective . The technology is already laid out , you just need incentive to buy it .” span >

The future energy profile of the UK transmission system

< span data contrast =” auto “> These new technologies offer the biggest change for grid balancers worldwide , as   domestic consumers   become more responsive in their power demands . Leslie said : “ Today , we dispatch generation to meet the demand curve , because historically , the generation is the part we can control . The   big change   is   in   making demand something we can control , because we ll have 10 million electric vehicles and many homes will have batteries . span >

[ caption id =” attachment_134382 align =” aligncenter width =” 620 “]< img class =” wp image 134382 src =” https :// www . power technology . com / wp content / uploads / sites / 7 / 2021 / 05 / CreditNationalGrid Pylon Maintenance South Wales PR High Res 450×340 . jpg alt =” Pylon maintenance works width =” 620 height =” 413 ” /> Physical transmission infrastructure in the UK is owned and operated by separate companies . Credit : National Grid .[/ caption ]

< span data contrast =” auto “>“ You could say this will flatten and suppress the peaks , I absolutely think that will happen . But equally , a peak could occur at four o clock on a Sunday morning , because that s when the wind is blowing the strongest and everybody s charging their vehicles , getting their hot water and heating ready , and getting some store of energy to heat their oven to cook their Sunday roast . span >

< span data contrast =” auto “>“ span >< span data contrast =” auto “> I think it s not so much a flattening of the curve , it s about matching the demand with when the generation span >< span data contrast =” auto “>  i span >< span data contrast =” auto “> s available .” span >

< span data contrast =” auto “> Leslie believes there   is still   a long way to go before weekday transmission demand starts   looking similar to that of the weekend He says : “ The demand shape will shift through other means , as we look to the future . Things like smart tariffs , and people being encouraged to consume energy when the sun is high , the wind is blowing in the right direction , and the demand is low .” span >

< em > Read about the changing profile of grid balancing in our article on half-hourly settlement. em >

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Free Report
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Delve into the renewable energy prospects for Morocco

In its new low greenhouse gas (GHG) emission strategy to 2050, submitted to the United Nations (UN), the Ministry of Energy Transition and Sustainable Development (MEM) of Morocco suggested to raise the share of renewable capacity in the country’s total power installed capacity mix to 80%.   Morocco currently aims to increase the share of renewables in total power capacity to 52% by 2030. The new strategy plans to increase the share of renewable capacity to 70% by 2040 and 80% by 2050.  GlobalData’s expert analysis delves into the current state and potential growth of the renewable energy market in Morocco. We cover: 
  • The 2020 target compared to what was achieved 
  • The 2030 target and current progress 
  • Energy strategy to 2050 
  • Green hydrogen 
  • Predictions for the way forward  
Download the full report to align your strategies for success and get ahead of the competition.   
by GlobalData
Enter your details here to receive your free Report.

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