RES Production of H2 Pathway to new energy landscape Gaelle Hotellier Executive Vice President Copyright © Siemens AG. All rights reserved

Big Picture Hydrogen Conversion of electrical into chemical power Generation Conversion In / Out Utilization Direct utilization w/o storage Fuel Cell Car H2 H2-Storage Mobility (H2-Fuel) O2 H2 H2 solar power + - Gaspipeline „Convergence“ Gas-Turbine Intermittent generation CH4 Energy (Re-Electrification) H2O PEM-Elektrolyzer injection CH4 * H2 wind power H2 Steady generation Methanation / CO2 utilization/ others Industry Industry (H2-Utilization) Grid CO2 fossile H2 drives the convergence between energy, industry & mobility markets *partially (in case of cheap power) 2 / 26

The PEM technology uses a robust polymer membrane as electrolyte Water Electrolysis Principle Basics Key specs PEM* technology DC current splits water into hydrogen and oxygen production rate is related to current 9 liters of water yield 1 kg of hydrogen approx. 50 kWh electrical energy generate 1 kg/h hydrogen 1 kg of hydrogen contain 33,3 kWh energy 2H20  2H2 + O2 H2O H2 O2 electrode gas-diffusion-layer bipolar plate PEM-electrolyte * Proton-Exchange-Membrane purpose: - ion conductor (H+) - electric isolator - gas-tight separator The PEM technology uses a robust polymer membrane as electrolyte

PEM Electrolyzers are technologically promising compared to alkaline technology Dynamic Maintenance + Size + + No caustic potash solution No leaching No precipitation Cycles 0 % .. 300 % without relevant aging High current density allows compact construction € Operability + Operating costs + No inert gas flushing No protective electrodes current No preheating Highest dynamic for lowest current prices Lifetime Pressure + + No caustic potash, less corrosion High System pressures Low compression costs Construction + Modular, scalable Industrial standards

PEM Electrolyzers @ Siemens Leading edge technology for high capacity electrolyzers Hydrogen: Enabling conversion between electrical and chemical energy Excess Energy Renewable Energy Chemical Energy PEM Electrolyzer Technology Siemens Expertise Robust polymer membrane as electrolyte Extremely dynamic and tolerant to overload even under pressurized operation High pressure operation without efficiency loss Operation as dynamic load for secondary and even primary control power Pure water – no leach on-off switching without any delay No N2-purge and preheating necessary PEM electrolyzer development started 1998 Reference list in electrolyzer technology: - continuous lab operation > 50.000 h - 10y field operation (prototype) - 100 bar prototype - 40y electrode know-how complete solution in one hand - heavy duty rectifiers (up to 70.000 A) - transformers - control units - grid connection - gas turbines

First Siemens electrolyzer units under operation at customer sites. 100 - 300 kW PEM Electrolyzer Demonstrator Key statements Under operation Rated power of the system is 100 kW, peak power 300 kW (electrical stack input) H2 and O2 are produced at an output pressure of 50 bar The container is a „self-sustaining“ system. Power supply as well as water purification are onboard The demonstrator was delivered 2012 to RWE in the context of the BMBF-funded project CO2RRECT* *CO2-Reaction using Regenerative Energies and Catalytic Technologies Siemens Elektrolyzer at the RWE site Niederaußem First Siemens electrolyzer units under operation at customer sites.

Control power - Additional path for PEM Technology as it is based a. o Control power - Additional path for PEM Technology as it is based a.o. on reaction time Transmission System operators (TSOs) are responsible for safe and reliable network operations in their respective control area. To fulfill the task “frequency stability”, TSOs need balancing power. The Control Power call takes place timely phased and is split between primary and secondary (or minutes reserve) regulation. Control Power can be either positive or negative (neg. =  consumption/  production; pos.=  production/  consumption) 2 business case opportunities: “demand price” (= stand-by) and “working price” (= release order) Interesting link: https://www.regelleistung.net/ip/action/index?language=en The Primary Control secure the rebalancing between produced and consumed power within seconds, whereat the frequency remains within the authorized limits. The objective of the Secondary Control is to put the frequency back to its desires value und the power transfer to the agreed values, and herewith to have the whole activated primary regulation available as reserve again In addition to the secondary regulation, the transmission grid operator need Minute reservel to restore free secondary balancing power range as well as the balancing of power deficits not being solved through secondary regulation only.

negative control power positive control power PEM Electrolyzers @ Siemens Operation as Control Power Startup time (blackstart) ~ 10 min From standby to full load in < 10 sec Full dynamic behavior between 0 and 300% electric load (positive, negative or combined mode control power) Power in % providing negative control power providing positive control power normal operation 300% negative Regellast: 200 % 200% 100% positive Regellast: 100 kW PEM electrolyzers can be operated as efficient dynamic load for secondary and even primary control power

Roadmap: PEM Electrolyzer Portfolio “SILYZER” 21 SILYZER – Electrolyzer Systems from Siemens Up-scaling Roadmap “SILYZER family” Roadmap: PEM Electrolyzer Portfolio “SILYZER” Key take away Product line I 0.1 – 0.3 MW Product line II 1 - >10 MW 2012 2014 2015 Rated Powernominal 1 MW 10 MW 100 MW 0,1 MW Product line III 10 - >100 MW 2018 Product line IB * 0.2 - >1 MW Siemens has established the business unit “Hydrogen Solutions” to develop and industrialize PEM electrolyzer systems. The Siemens PEM- electrolyzers will be cost- competitive to alkaline technology. Modular Systems in the MW-range will be available starting 2015, demonstrators in the sub- MW-class in 2013. SILYZER 100 SILYZER 100 SILYZER 200 SILYZER 300

I DT LD HY Industry Sector Drives Technology Division Hydrogen Solutions contact: Gaelle Hotellier (Executive VP & General Manager) +49 9131 7-22847 mailto:gaelle.hotellier@siemens.com Copyright © Siemens AG. All rights reserved