6 11 Other technology breakthroughs enabled by NFM Metals will continue to play an important role in other technologies e g batteries CCU that will be crucial for achieving a climate neutral economy Some e xamples of metals related innovations in other technologies are given below Molten metal batteries Liquid metal batteries were born from the practice of electrochemical aluminium smelting electricity in aluminium from o xide out but operating in reverse Electrons come from the lighter metal on top where the corresponding ions are travelling downwards through the electrolyte in order to recombine with the electrons at the boundary of the heavier liquid metal at the bottom For the rest no mixing tak es places and the three layers remain sepa rate During discharge the top layer gets thinner and bottom layer thick er during charging this process reverses Degrading of the system is nearly absent 232 Thermally regenerative batteries Copper could be used in new fashions to reduce the global energy footprint L arge amounts of lowgrade waste heat 130C are currently released during many industrial geothermal and solarbased processes Thermally regenerative batteries TRBs can convert this waste heat into electrical power Thermally regenerative ammoniabased batteries TRABs as well as acetonitrilebased batteries based on copper electrodes have been developed to produce electrical current from the formation of copperammonia or copperacetonitrile comple x using waste heat to regenerate the process 233 234 The new TRAB technology can be applied to convert lowgrade waste heat which cannot be used for any other application into power The process increases the efciency of the manufacturing industry and reduces its carbon emissions It is estimated that in Europe alone TRAB technology could generate about 6 TWh of elec tricity per annum This is comparable to the electricity generated by solar panels in Europe in 2010 or almost 10 of the electricity use of the nonferrous metals sector in 2017 Metals based fow batteries R edo x fow batteries RFBs are a type of electrochemical energy storage device This means they store electrical energy in chemical form and subsequently dispense this energy in electrical form via a spontaneous reverse redo x reaction of dissolved ions in positive and negative electrolytes These electrolytes are collected in e xternal tank s and pumped into a power module for charge and discharge The concept is modular and highly scalable 232 Ambri 233 Fraunhofer ISI 2019 234 CUBES BO X 14 Boliden sectoral symbiosis in W estern Finland Boliden is capturing e x cess heat and supplying it to district heating network s in large quanti ties The K okk ola Industrial P ark KIP in western Finland is one of best e xamples in Europe of how industrial synergies developed since the 1960s contribute to a circular economy originally based on meeting practical needs and reducing costs The companies located in the KIP are intrinsically link ed with one another with many synergies based on material and resource fows in closed systems Ex cess heat and steam from the Boliden K okk ola zinc smelter are used to generate municipal district heating and electricity Sulphuric acid produced at Boliden s sulphuric acid plant is used as a raw material by other companies in the KIP Boliden sells the steam it produces in the zinc roasting process to the municipal energy company that generates electricity from the steam In 2017 320 000 MWh of steam from Boliden was used to produce electricity district heating and lowpressure steam for industrial partners in KIP and local households In 2017 around 125000 MWh of heat from the sulphuric acid plant was delivered to the municipal heating plant which is enough to heat appro ximately 6000 homes as well as some buildings in the industrial park 231 231 Boliden ND MET ALS IN A CLIMA TE NEUTRAL EUROPE A 2050 BL UEPRINT 62