Image: Copernicus projects

These five tech­nolo­gies are designed to make the pow­er grid fit for the ener­gy transition

The Kopernikus project ENSURE is research­ing tech­nolo­gies to equip the pow­er grid for the ener­gy tran­si­tion. Now the project has announced the first tech­nolo­gies it will test for the first time in the com­ing years.

One thing is cer­tain: the ener­gy tran­si­tion can­not suc­ceed with the ener­gy grid in its cur­rent form: As the share of renew­able ener­gies increas­es, the pow­er fluc­tu­a­tions in the grid will also increase sig­nif­i­cant­ly. In addi­tion, many small elec­tric­i­ty sup­pli­ers are replac­ing a few large ones. And: Net­works must be able to trans­port elec­tric­i­ty in two direc­tions at the same time. In order to meet these require­ments, the Kopernikus project ENSURE, fund­ed by the Fed­er­al Min­istry of Edu­ca­tion and Research, is devel­op­ing tech­nolo­gies for the ener­gy grid of the future. To this end, ENSURE has analysed by 2019 which require­ments elec­tric­i­ty grids will have to meet by 2050. Since then, it has been devel­op­ing solu­tions to meet these require­ments. Now the project has announced the first five tech­nolo­gies it will test in real-world or dig­i­tal­ly sim­u­lat­ed set­tings. The tech­nolo­gies at a glance:

1. the ENSURE adap­tive protection
To pro­tect the pow­er grid, pro­tec­tion devices per­ma­nent­ly mea­sure cur­rents and volt­ages in the grid. If faults occur, they shut down the affect­ed areas. The prob­lem: Until now, pro­tec­tion devices have been pro­grammed once — and then always work accord­ing to the same rules. This pre­vents them from react­ing to changes in the net­work. ENSURE adap­tive pro­tec­tion is designed to change that: It net­works sev­er­al pro­tec­tion instru­ments, allows their data streams to con­verge cen­tral­ly and con­tin­u­ous­ly cal­cu­lates set­ting para­me­ters that match the cur­rent net­work sit­u­a­tion. This means that the pro­tec­tion sys­tem is con­stant­ly learn­ing and can react flex­i­bly to the feed-in of renew­able energies.

2. the ENSURE sol­id state transformer
The pow­er grid works with alter­nat­ing cur­rent, e‑cars need direct cur­rent. So far, e‑car charg­ing sta­tions can only be con­nect­ed to the pow­er grid via sev­er­al con­ver­sion steps. The ENSURE sol­id-state trans­former is designed to change that. It has a so-called con­vert­er already inte­grat­ed, which con­verts alter­nat­ing cur­rent into direct cur­rent. Thanks to this smart solu­tion for direct con­nec­tion to the grid, there are sig­nif­i­cant­ly few­er ener­gy loss­es on the path of the elec­tric­i­ty from the grid to the car.

3. ENSURE’s MVDC close-cou­pling simulator
Up to now, medi­um-volt­age grids have been divid­ed into sub-grids. If a fault occurs, pow­er fail­ures can eas­i­ly be lim­it­ed local­ly. The prob­lem is that the grids are hard­ly flex­i­ble as a result and can­not exchange ener­gy with each oth­er. For exam­ple, wind tur­bines may have to be switched off in one sub-grid because the grid is over­loaded, while capac­i­ty is still avail­able in the neigh­bour­ing sub-grid. ENSURE’s inno­v­a­tive MVDC close cou­plings are designed to change that. They enable the per­ma­nent exchange of ener­gy reserves between indi­vid­ual sub­net­works — and still ensure that faults can­not spread to neigh­bour­ing sub­net­works. ENSURE first tests them through a dig­i­tal simulation.

4. the ENSURE mesh­ing concept
Up to now, Ger­many’s ener­gy grid has large­ly been orga­nized along radi­at­ing lines: Cen­tral pow­er plants deliv­er ener­gy to all parts of Ger­many. If the beams of these stars are inter­con­nect­ed in the future like the mesh­es of a net­work, the ener­gy can also be deliv­ered to its des­ti­na­tion via many oth­er routes — and this much more effi­cient­ly and at rel­a­tive­ly low net­work expan­sion costs. Analy­ses from ENSURE show that smart mesh­ing can help meet the chang­ing demands of ener­gy pro­duc­tion and con­sump­tion. Now ENSURE wants to test its mesh­ing con­cept at dis­tri­b­u­tion grid lev­el in practice.

5. ENSURE’s dig­i­tal substation
In the pow­er grid, sub­sta­tions are some­thing like cross­roads. Dif­fer­ent net­works with dif­fer­ent volt­ages meet here. The task is to man­age the elec­tric­i­ty in such a way that the grids func­tion sta­bly. To make this work, it helps to know how the actu­al pow­er flows with­in a sub­sta­tion. The more retriev­able infor­ma­tion there is, the bet­ter this infor­ma­tion can be deter­mined. ENSURE has devel­oped a dig­i­tal sub­sta­tion pre­cise­ly for this pur­pose. New mea­sur­ing devices and mod­ern com­mu­ni­ca­tion tech­nol­o­gy dig­i­tal­ly record data from indi­vid­ual sub­sta­tion com­po­nents, eval­u­ate it, and process it quick­ly and effi­cient­ly — in order to be able to con­trol pow­er flows bet­ter than before and auto­mat­i­cal­ly on the basis of this data.

By 2022, ENSURE aims to test these tech­nolo­gies for the first time. Sub­se­quent­ly, these are to be expand­ed and sup­ple­ment­ed by fur­ther technologies.