“Bayernwerk is the engine room of the energy transition.”

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Looking back, how important was the invention of the high-speed resistor-type tap changer?

Quite clear­ly, it’s often the more hid­den things that achieve great things. Who – apart from tech enthu­si­asts – would think of rev­o­lu­tion­ary devel­op­ments when hear­ing about high-speed resis­tor-type tap chang­ers? But that’s exact­ly what we’re talk­ing about. Grid oper­a­tion as we know it today would not have been tech­ni­cal­ly or eco­nom­i­cal­ly fea­si­ble with­out the inven­tion of the high-speed resis­tor-type tap chang­er. It was this inven­tion that first made it pos­si­ble to imple­ment large, inter­con­nect­ed grids in prac­tice and main­tain sta­ble volt­age over long dis­tances.

The inven­tion of the high-speed resis­tor-type tap chang­er 100 years ago was thus one of the deci­sive tech­no­log­i­cal break­throughs and a key inno­va­tion for the devel­op­ment of mod­ern pow­er grids. This tap chang­er, which was nov­el at the time, made it pos­si­ble to pre­cise­ly reg­u­late trans­form­ers under load and thus sta­bly inter­con­nect dif­fer­ent volt­age lev­els. For today’s Bay­ern­werk AG and our pre­de­ces­sor orga­ni­za­tions, this inno­va­tion was of fun­da­men­tal impor­tance because it cre­at­ed the con­di­tions nec­es­sary to devel­op a high-per­for­mance, inte­grat­ed pow­er grid from a mul­ti­tude of indi­vid­ual region­al ener­gy sup­ply solu­tions. The high-speed resis­tor-type tap chang­er also made it pos­si­ble to pre­cise­ly con­trol load flows, which ulti­mate­ly led to the qual­i­ty and reli­a­bil­i­ty of today’s pow­er sup­ply. Look­ing back, it can there­fore be said that this inven­tion went far beyond its imme­di­ate tech­ni­cal ben­e­fits.

Rather, it laid the foun­da­tion for scal­ing up the ener­gy sup­ply and – as we must rec­og­nize – there­by also for the indus­tri­al­iza­tion of the Free State of Bavaria. Bern­hard Jansen’s high-speed resis­tor-type tap chang­er is not an obso­lete rel­ic even in today’s inno­v­a­tive dis­tri­b­u­tion net­work oper­a­tions, but rather a proven fun­da­men­tal com­po­nent. While its direct dom­i­nance is wan­ing in dynam­ic, decen­tral­ized net­works, its con­cep­tu­al sig­nif­i­cance remains cen­tral because a large part of today’s volt­age reg­u­la­tion tech­nol­o­gy is based on it or has evolved from it.

Bayernwerk AG and Reinhausen have been collaborating for decades. What connects the two companies?

When we talk about the con­nec­tion between our com­pa­nies, we quick­ly come back to the high-speed resis­tor-type tap chang­er and its inven­tor, Dr.-Ing. Bern­hard Jansen. And in doing so, we encounter a sto­ry that’s almost like a fairy tale. In Novem­ber 1928, Jansen took up the posi­tion of tech­ni­cal direc­tor at Oberp­falzw­erke AG für Elek­triz­itätsver­sorgung (OWAG) in Regens­burg, one of the pre­de­ces­sor com­pa­nies of today’s Bay­ern­werk.

Jansen held the patent for his high-speed resis­tor-type tap chang­er but until then it had remained pure­ly the­o­ret­i­cal. There was a short­age of high-qual­i­ty gears for his cou­pled dou­ble-gear mech­a­nism designed for step-by-step reg­u­la­tion of trans­form­ers under load. If tra­di­tion is to be believed, Jansen walked into the work­shop of Oskar and Richard Scheubeck in Rein­hausen a year lat­er and, accord­ing to the sto­ry, an appren­tice of the Scheubeck broth­ers achieved in just one day what no one had man­aged to do before. Vis­i­bly impressed, OWAG CEO Jansen then promised the broth­ers fur­ther orders. I think this sto­ry about the ear­ly days of our col­lab­o­ra­tion is emblem­at­ic of every­thing that fol­lowed.

Over the years, a trust­ing col­lab­o­ra­tion has devel­oped that goes far beyond a tra­di­tion­al sup­pli­er rela­tion­ship and is instead based on a part­ner­ship in devel­op­ing solu­tions for a con­tin­u­ous­ly evolv­ing ener­gy sys­tem. In my opin­ion, this is found­ed on a shared under­stand­ing of the cen­tral role of tech­nol­o­gy in ener­gy sup­ply, as well as high stan­dards of qual­i­ty, reli­a­bil­i­ty, and inno­va­tion. And if I may broad­en the per­spec­tive a bit, with a nod to the appren­tice from 1929: sup­port­ing young peo­ple, let­ting them just give it a try, and allow­ing their uncloud­ed per­spec­tives on chal­lenges to enable inno­va­tion – that suits us well today more than ever.

In your view, what are the most important milestones in the collaboration with Reinhausen?

These mile­stones can be traced along the major devel­op­men­tal stages of the ener­gy sup­ply sec­tor. In the ear­ly phase of grid expan­sion, the focus was ini­tial­ly on the tech­ni­cal pre­req­ui­sites for devel­op­ing a sta­ble inter­con­nect­ed grid from frag­ment­ed struc­tures – a feat made pos­si­ble in par­tic­u­lar by the intro­duc­tion of adjustable trans­form­ers and the tran­si­tion to uni­form volt­age lev­els. After World War II, the effec­tive­ness of these con­cepts became evi­dent in the rapid recon­struc­tion and reor­ga­ni­za­tion of the pow­er sup­ply, dur­ing which exist­ing grid seg­ments could be quick­ly rein­te­grat­ed into a func­tion­ing over­all sys­tem.

In the 1950s, a phase of strong growth fol­lowed, dur­ing which the grid was mas­sive­ly expand­ed, and sup­ply was sig­nif­i­cant­ly extend­ed across the coun­try, as reflect­ed, among oth­er things, in a mul­ti­pli­ca­tion of grid lengths and the num­ber of trans­former sta­tions. At the same time, projects such as the pumped-stor­age plant on the Pfreimd Riv­er in the Schwan­dorf coun­ty of Bavaria cre­at­ed flex­i­bil­i­ty options ear­ly on that now play a cen­tral role again in the con­text of the ener­gy tran­si­tion. Here, too, we once again encounter the vision­ary Bern­hard Jansen, who was the ini­tia­tor of the pow­er plant group. It was not with­out rea­son that OBAG renamed the pow­er plant com­plex on the Pfreimd the “Jansen Pumped-Stor­age Plant Group” in May 1959.

This devel­op­ment illus­trates that col­lab­o­ra­tion has always been par­tic­u­lar­ly influ­en­tial when tech­no­log­i­cal inno­va­tion and sys­temic devel­op­ment have been able to inter­lock. Here’s anoth­er exam­ple of con­sis­ten­cy: For more than 50 years, we have used almost exclu­sive­ly Rein­hausen on-load tap-chang­ers in our trans­form­ers. Our experts from the sub­sta­tion oper­a­tions team are full of praise: “These devices last the entire lifes­pan of a trans­former!” And the devel­op­ment of vac­u­um switch­ing tubes was a bril­liant move – now even less main­te­nance is required.

What are the biggest challenges currently facing Bayernwerk AG?

Our work is shaped by the dynam­ics of the ener­gy tran­si­tion, which is trans­form­ing the ener­gy sys­tem at a pace that is his­tor­i­cal­ly unprece­dent­ed. And we have to keep up with this pace – which we are doing. The mas­sive expan­sion of renew­able ener­gy, par­tic­u­lar­ly decen­tral­ized gen­er­a­tion facil­i­ties, is lead­ing to increas­ing volatil­i­ty and com­plex­i­ty in grid oper­a­tions. On the Bay­ern­werk Netz GmbH grid alone, there are cur­rent­ly more than one mil­lion renew­able ener­gy instal­la­tions, the vast major­i­ty of which are PV sys­tems.

In total, near­ly 24,000 megawatts of renew­able capac­i­ty are direct­ly con­nect­ed to the Bay­ern­werk Netz GmbH grid today. But that’s not all: We expect renew­able gen­er­a­tion capac­i­ty in Bavaria to triple by 2045. Dur­ing the same peri­od, we antic­i­pate that elec­tric­i­ty con­sump­tion will dou­ble, and we are also see­ing a surge in inquiries from large con­sumers such as data cen­ters, par­tic­u­lar­ly in the Munich area and the Würzburg/Aschaffenburg region.  The ener­gy sys­tem is thus becom­ing the cen­tral plat­form for dig­i­tal trans­for­ma­tion. That’s a game chang­er. Anoth­er game chang­er is flex­i­bil­i­ty.

What do you mean by “flexibility”?

Stor­age solu­tions. In terms of stor­age capac­i­ty, we’re rapid­ly approach­ing about 50 per­cent of our peak load of 8,000 megawatts across all seg­ments, dri­ven by strong growth in res­i­den­tial and green ener­gy stor­age sys­tems. Bavaria, the “land of stor­age,” is thus flour­ish­ing. In a sense, this rais­es ques­tions sim­i­lar to those that arose in the ear­ly phase of elec­tri­fi­ca­tion – name­ly, how dif­fer­ent gen­er­a­tion and con­sump­tion struc­tures can be effi­cient­ly inte­grat­ed and oper­at­ed in a sta­ble man­ner. The cru­cial dif­fer­ence, how­ev­er, lies in the speed and scale at which this trans­for­ma­tion is tak­ing place. Today, this trans­for­ma­tion is occur­ring not over decades, but with­in just a few years.

At the same time, we are wit­ness­ing the shift from a cen­tral­ized to a decen­tral­ized ener­gy sys­tem – a sys­tem we described many years ago in our “Flower-Pow­er” con­cept. Back then, Flower-Pow­er was the vision of a sys­tem in which the rur­al “leaves,” with their high gen­er­a­tion capac­i­ty, sup­ply the urban “flower,” with its high demand. A sys­tem with local ener­gy cycles made pos­si­ble by flex­i­bil­i­ty. In oth­er words: The ener­gy tran­si­tion is tak­ing place in rur­al areas. And we’re see­ing more and more “Flex­umers” – peo­ple who not only con­sume and pro­duce ener­gy but also store it, use it them­selves, or make it avail­able close to the point of gen­er­a­tion. That’s true local ener­gy. And that’s what makes the ener­gy sys­tem of the future a real hit.

How exactly is Bayernwerk AG managing the energy transition and the transformation of the grids?

The Bay­ern­werk Group is address­ing these chal­lenges with an inte­grat­ed approach that con­sis­tent­ly com­bines grid expan­sion, sys­tem inte­gra­tion, and dig­i­tal­iza­tion. In 2022, we launched the “Growth Ini­tia­tive: Bavaria’s Ener­gy Future,” and we are stead­fast­ly con­tin­u­ing on this path, invest­ing approx­i­mate­ly 12 bil­lion euros in Bavaria’s ener­gy tran­si­tion from 2026 to 2030. Last year alone, we expand­ed the capac­i­ty of 15 sub­sta­tions, installed over 1,700 dig­i­tal local net­work sta­tions, laid 177 kilo­me­ters of high-volt­age lines, near­ly 1,600 kilo­me­ters of medi­um-volt­age cables, and an addi­tion­al 1,600 kilo­me­ters of low-volt­age cables. These are fig­ures that were com­plete­ly unthink­able just a few years ago — seem­ing­ly far removed from real­i­ty. Today, they are a real­i­ty. And this trend will con­tin­ue in the com­ing years.

The expan­sion of the grid infra­struc­ture thus cre­ates the nec­es­sary capac­i­ty for feed­ing renew­able ener­gy into the grid, while at the same time bring­ing addi­tion­al flex­i­bil­i­ty to the sys­tem through the inte­gra­tion of stor­age sys­tems. A word specif­i­cal­ly on large-scale stor­age sys­tems: We must pro­ceed with cau­tion here, as they inter­act with the pub­lic grid. Stor­age sys­tems oper­at­ed sole­ly based on mar­ket-dri­ven objec­tives can place a strain on the grid. And any­thing that exac­er­bates exist­ing grid bot­tle­necks is prob­lem­at­ic. We there­fore pre­fer grid-neu­tral and grid-sup­port­ing stor­age solu­tions. We’re cur­rent­ly fac­ing a moun­tain of appli­ca­tions for large-scale bat­tery stor­age – with a capac­i­ty that sim­ply can­not and will not be real­ized.

We’re cur­rent­ly talk­ing about over 80,000 megawatts, well over ten times our peak load. It’s impor­tant to sep­a­rate the wheat from the chaff here and, above all, to remain real­is­tic. Large-scale stor­age sys­tems still require sys­temic and tech­ni­cal reg­u­la­tions. This is an ongo­ing devel­op­ment process. More­over, it’s not just about stor­age. We’re also look­ing at data cen­ters, the eco­nom­ic devel­op­ment of com­merce and indus­try, decar­boniza­tion, hous­ing con­struc­tion, dig­i­tal­iza­tion, heat sup­ply, e‑mobility for pas­sen­ger cars, and soon for trucks – all of which need elec­tric­i­ty, all of which need the grid. This cre­ates a log­i­cal rush for grid capac­i­ty, which is increas­ing­ly turn­ing it into the “gold” of the ener­gy tran­si­tion. 

In your view, what are the most important technical and organizational levers for managing this dynamic?
 

The cen­tral chal­lenge today is to make the increas­ing com­plex­i­ty of the ener­gy sys­tem man­age­able. We have unleashed renew­ables. We have unleashed the grids. Now the goal is to unleash the entire ener­gy sys­tem. To achieve this, we are rely­ing on a com­bi­na­tion of tech­no­log­i­cal and orga­ni­za­tion­al levers. Dig­i­tal­iza­tion plays a key role here, as it enables near-real-time grid con­trol for the first time, there­by cre­at­ing the pre­req­ui­site for active sys­tem man­age­ment. At the same time, process­es are being stan­dard­ized and scaled to imple­ment the nec­es­sary expan­sion at the required pace.

For exam­ple, we have defined stan­dard sizes for sub­sta­tions, are com­mit­ted to long-term, reli­ably pre­dictable col­lab­o­ra­tion with our part­ner com­pa­nies, have revamped our inven­to­ry and logis­tics man­age­ment, and are adapt­ing our IT process­es on an enor­mous scale – because for us as a grid oper­a­tor, the ener­gy tran­si­tion means, above all, mass process­es. In addi­tion, for­ward-look­ing plan­ning based on data analy­sis and sce­nar­ios is becom­ing increas­ing­ly impor­tant, as it helps us antic­i­pate future devel­op­ments ear­ly on. Over­all, this cre­ates a sys­tem that remains sta­ble and con­trol­lable despite grow­ing dynam­ics.

One exam­ple of this is the use of arti­fi­cial intel­li­gence, which helps us effi­cient­ly uti­lize the grid based on real-time data and thus make opti­mal use of avail­able capac­i­ty. We are Germany’s first dis­tri­b­u­tion net­work oper­a­tor to build a grid-sup­port­ing stor­age facil­i­ty, which is sched­uled to go into oper­a­tion this year in the Cham dis­trict. We are dri­ving inno­va­tion for­ward: With the “feed-in-sock­et” con­cept, we are proac­tive­ly and strate­gi­cal­ly pro­vid­ing capac­i­ty for con­nect­ing renew­able ener­gy sources.

This inte­gra­tion enables the opti­mized use of grid con­nec­tion points – for exam­ple, by con­nect­ing wind pow­er to an exist­ing PV feed-in point. In sum­ma­ry, our orga­ni­za­tion­al and tech­no­log­i­cal inno­va­tion is cru­cial for bal­anc­ing tomorrow’s ener­gy sys­tem and get­ting it up and run­ning prop­er­ly.

What are your expectations today regarding collaboration with manufacturers and technology partners such as Reinhausen?

Expec­ta­tions for part­ners like Rein­hausen have expand­ed sig­nif­i­cant­ly in the wake of the ener­gy system’s trans­for­ma­tion and are now more strate­gi­cal­ly ori­ent­ed than ever before. In addi­tion to high prod­uct qual­i­ty and reli­a­bil­i­ty, what mat­ters increas­ing­ly is the abil­i­ty to joint­ly dri­ve tech­no­log­i­cal devel­op­ments and to con­ceive of solu­tions that span the entire life­cy­cle of sys­tems. This also includes the inte­gra­tion of dig­i­tal func­tions that enable equip­ment to be intel­li­gent­ly inte­grat­ed into the over­all sys­tem. His­tor­i­cal­ly, close col­lab­o­ra­tion between grid oper­a­tors and tech­nol­o­gy part­ners has already been a key suc­cess fac­tor in build­ing out the ener­gy sup­ply infra­struc­ture.

This log­ic applies today more than ever, because the trans­for­ma­tion of the grids can only suc­ceed through close col­lab­o­ra­tion among all stake­hold­ers. That is why we are also increas­ing our involve­ment in research projects. And we are estab­lish­ing new com­mu­ni­ca­tion for­mats. For exam­ple, our “Partner.Live: Tech­nikDi­a­log” cel­e­brat­ed its pre­miere at the end of April. More than 160 rep­re­sen­ta­tives from part­ner com­pa­nies, uni­ver­si­ties, and research insti­tu­tions came togeth­er to dis­cuss future tech­ni­cal top­ics in the ener­gy and grid sec­tors. The goal: to bridge the gap between the­o­ry and prac­tice, gen­er­ate momen­tum, fur­ther devel­op ideas, and fos­ter col­lab­o­ra­tion. It goes with­out say­ing that Rein­hausen was there to present its dynam­ic set­point con­trol for adjustable local net­work trans­form­ers. Thank you very much for that!

In gen­er­al, one thing is clear to me: The ener­gy tran­si­tion is a col­lec­tive effort. It is arguably the largest dig­i­tal­iza­tion project of our time. And it is a mas­sive trans­for­ma­tion process. The ener­gy tran­si­tion will only suc­ceed if all stake­hold­ers under­stand their roles and are pre­pared to make their respec­tive con­tri­bu­tions as part of a com­mu­ni­ty of respon­si­bil­i­ty. Bay­ern­werk is the engine room of the ener­gy tran­si­tion. We are able to do this thanks to long-stand­ing part­ners like Rein­hausen.

I read on the Rein­hausen web­site: “Our mis­sion is true inno­va­tion: Togeth­er with our cus­tomers, we are shap­ing the ener­gy tran­si­tion.” I whole­heart­ed­ly agree with that. We share val­ues such as trust, reli­a­bil­i­ty, and com­mit­ment. I think that’s at least as impor­tant as tech­ni­cal inno­va­tion. I appre­ci­ate that very much. And I’m also very grate­ful for it. Togeth­er, we’re shap­ing the future of our grids – with tech­nolo­gies that set new stan­dards and con­cepts that enable growth.