With the flow of Time

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1926 — 1949

Large scale electrification begins

The key foun­da­tions of elec­tri­fi­ca­tion are laid by the 1920s: In 1866, Wern­er von Siemens makes elec­tric­i­ty gen­er­a­tion pos­si­ble using the dynamo-elec­tric prin­ci­ple. About a decade lat­er Thomas Edi­son makes the incan­des­cent light bulb suit­able for every­day use. And with the devel­op­ment of the trans­former in the 1880s alter­nat­ing cur­rent tech­nol­o­gy becomes the stan­dard for pow­er trans­mis­sion. The streets of major cities now glow with elec­tric light, and in more and more fac­to­ries, elec­tric­i­ty pow ers machines and dri­ves. But appear­ances are deceiv­ing: the gen­er­al pop­u­la­tion, espe­cial­ly in rur­al areas, still has no access to elec­tric­i­ty Uni­form stan­dards are also lack­ing, and the elec­tric­i­ty land­scape resem­bles a patch­work quilt, with pow­er gen­er­a­tion and con­sump­tion tak­ing place local­ly. Fur­ther­more, even where pow­er is already avail­able, the sup­ply is unsta­ble. Trans­form­ers that can be adjust­ed under load are intend­ed to change this. Although there are ini­tial attempts using tap chang­ers based on the reac­tor prin­ci­ple, they are tech­ni­cal­ly very com­plex.

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1950 — 1970

The years of the economic miracle – Today’s power grid takes shape

In the two decades fol­low­ing World War II, the glob­al econ­o­my grows rapid­ly – and with it, the demand for elec­tric­i­ty. Not only indus­try but also pri­vate house­holds require ever more ener­gy, as elec­tri­cal appli­ances such as wash­ing machines, refrig­er­a­tors, and tele­vi­sions grad­u­al­ly become stan­dard house­hold items. Dur­ing this peri­od, pow­er grids in Europe evolve from region­al sup­ply struc­tures into large-scale, nation­al, inter­con­nect­ed pow­er grids, and inter­na­tion­al grid coor­di­na­tion is also being pro­mot­ed as ear­ly as the 1950s. Both devel­op­ments neces­si­tate phase shifters for load flow con­trol, which can­not oper­ate with­out tap chang­ers. With high-volt­age direct cur­rent (HVDC) trans­mis­sion, a new tech­nol­o­gy grad­u­al­ly gains accep­tance for trans­port­ing elec­tric­i­ty over long dis­tances with low loss­es. With­out tap chang­ers in the con­vert­er sta­tions, this is not eco­nom­i­cal­ly viable.

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1971 — 1989

Expansion and new consumers

In the 1970s and 1980s, the expan­sion of pow­er grids con­tin­ues world­wide, though the focus shifts from that of the post­war peri­od. Where­as pre­vi­ous­ly the empha­sis had been on build­ing nation­al grids, the focus now increas­ing­ly turns to inter­con­nect­ing large pow­er sys­tems. High-volt­age and extra-high-volt­age trans­mis­sion lines are built across bor­ders to bal­ance peak loads, share reserve capac­i­ty, and increase the reli­a­bil­i­ty of sup­ply. The 1973 oil cri­sis also marks an impor­tant turn­ing point in ener­gy sup­ply – to become less depen­dent on oil, the expan­sion of nuclear ener­gy is accel­er­at­ed world­wide. A phase of tech­no­log­i­cal mod­ern­iza­tion also begins – the increas­ing avail­abil­i­ty of com­put­ers auto­mates grid con­trol cen­ters, and SCADA sys­tems enable large-scale remote mon­i­tor­ing and con­trol of pow­er grids in real time for the first time.

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1990 — 2000

Liberalization of the electricity markets

The 1990s are a time of new begin­nings: The Iron Cur­tain has fall­en, com­put­ers are increas­ing­ly shap­ing the work­place, the World Wide Web goes online, the dig­i­tal age begins, and the mobile phone gains wide­spread accep­tance there­by per­ma­nent­ly trans­form­ing com­mu­ni­ca­tion. In many coun­tries, par­tic­u­lar­ly in Europe, elec­tric­i­ty mar­kets are being lib­er­al­ized, and gen­er­a­tion, trans­mis­sion, and dis­tri­b­u­tion are being sep­a­rat­ed. At the same time, inter­na­tion­al inter­con­nec­tion is increas­ing, and with it, the cross-bor­der elec­tric­i­ty trade. The grow­ing num­ber of play­ers and trade flows sig­nif­i­cant­ly increase the com­plex­i­ty of grid oper­a­tion and neces­si­tate more com­put­er-aid­ed con­trol. Progress is also being made in the tech­ni­cal devel­op­ment of renew­able ener­gy gen­er­a­tion. A mile­stone is the world’s first off­shore wind farm, which goes into oper­a­tion in Den­mark in 1991.

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from 2001

The energy transition gains momentum

Since the 2000s, more and more solar and wind farms have been built and PV sys­tems installed on rooftops, and the share of renew­able ener­gy in the over­all ener­gy mix is steadi­ly increas­ing. The expan­sion of HVDC lines is pro­gress­ing to trans­port ener­gy gen­er­at­ed by off­shore wind farms or in remote gen­er­a­tion regions to con­sump­tion cen­ters. The rapid expan­sion of renew­able ener­gy, par­tic­u­lar­ly wind and solar pow­er, is lead­ing to more decen­tral­ized and volatile elec­tric­i­ty gen­er­a­tion. Pre­vi­ous­ly uni­di­rec­tion­al load flows are now becom­ing increas­ing­ly bidi­rec­tion­al, espe­cial­ly in the dis­tri­b­u­tion grid sec­tor. And with the rise of elec­tric mobil­i­ty, new con­sumers are being added. All of this makes the reg­u­la­tion of dis­tri­b­u­tion grids nec­es­sary. At the same time, the infra­struc­ture in many loca­tions is reach­ing a crit­i­cal age, and mon­i­tor­ing solu­tions and main­te­nance ser­vices for equip­ment are thus gain­ing in impor­tance.

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to 2126

Looking to the future

A world with­out elec­tric­i­ty has long been unthink­able – com­mu­ni­ca­tion, trans­porta­tion, our work, and our entire lives depend on a reli­able pow­er sup­ply. In the com­ing decades, pow­er grids face a fun­da­men­tal trans­for­ma­tion. It is already clear today that glob­al elec­tric­i­ty demand will dou­ble by 2050 – dri­ven by the elec­tri­fi­ca­tion of the mobil­i­ty and heat­ing sec­tors, our hunger for data, and the use of arti­fi­cial intel­li­gence. At the same time, the com­plex­i­ty of the grids is increas­ing due to the con­tin­ued expan­sion of renew­able ener­gy. New tech­nolo­gies will be nec­es­sary to meet these chal­lenges. Whether it’s super­con­duct­ing cables, local direct-cur­rent grids, smart con­trol sys­tems, or large-scale stor­age solu­tions – the indus­try is work­ing dili­gent­ly to devel­op the flex­i­ble, dig­i­tal, and resilient grids of the future.