Decarbonizing distributed power solutions - vgb.org

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VGB PowerTech 12 l 2020 Decarbonizing distributed power solutions

Decarbonizing distributed power solutions

AuthorsDr. techn. Dipl.-Ing. Klaus PayrhuberDr. techn. Dipl.-Ing. Stephan LaimingerDipl.-Ing. Herbert SchaumbergerDipl. Wi.-Ing. Carl RichersDipl.-Ing. Dipl. Wirtsch.-Ing. Martin SchneiderINNIO Jenbacher GmbH & Co OG Jenbach, Austria

Decarbonizing distributed power solutions Klaus Payrhuber, Stephan Laiminger, Herbert Schaumberger, Carl Richers and Martin Schneider

Kurzfassung

Dekarbonisierung dezentraler Stromerzeugung

Das Ziel der Klimaneutralität bis 2050 erfor-dert große Anstrengungen – vor allem im Aus-bau der volatilen erneuerbaren Energiequellen Wind und Sonne. Dabei wird es in der EU zu einer massiven Überbauung kommen und über-schüssiger erneuerbarer Strom muss in Zeiten von Überangebot zu Zeiten von Unterversor-gung verschoben werden. Batterien sind dafür nur eingeschränkt geeignet. Vor allem bei der saisonalen Energiespeicherung im TWh-Be-reich soll Wasserstoff eine große Rolle spielen, insbesondere grüner Wasserstoff. Denn Wasser-stoff kann direkt in technischen oder in natürli-chen Speichern zwischengespeichert werden. Wasserstoff kann z.B. in den Sektoren Verkehr und Industrie direkt eingesetzt werden, oder aber für die Rückverstromung verwendet wer-den. Synthetisches Gas oder chemische Produk-te wie Methanol oder Ammoniak sind Wasser-stoffprodukte, die fossile Brennstoffe ersetzen oder als Energiespeichermedien dienen können.Gasmotoren wurden in den vergangenen Jahr-zehnten für Erdgas und Sondergase (Biogas, Klärgas, Deponiegas) entwickelt und haben aufgrund ihrer kompakten Bauweise und ih-rem hohen Gesamtnutzungsgrad von mehr als 90 % ein weit gestreutes Einsatzgebiet. Bereits in der Vergangenheit wurden Gasmotoren mit Sondergasen mit hohem Wasserstoffanteil be-trieben, z.B. mit Koksgas oder Synthesegas aus der Biomassevergasung. Versuche mit Wasser-stoffzumischung gibt es schon seit mehr als 30 Jahren. Derzeit werden Demonstrationsanla-gen mit bis zu 60 %(v) und auch mit 100 % Wasserstoff umgesetzt.Gasmotoren sind heute schon für Wasserstoff-anwendungen verfügbar. Bis Serienprodukte mit der gewohnten Zuverlässigkeit angeboten werden können, ist allerdings noch mehr Felderfahrung bei kontinuierlichem Betrieb mit Wasserstoff anstelle von Erdgas nötig. l

Introduction

Europe is aiming for carbon neutrality by 2050, but the energy transition is not just an EU initiative. Countries inside the EU and globally are setting targets to reach carbon neutrality even before 2050. It is a global transition that is centered on the transformation from a largely fossil-based to a low or carbon neutral energy system. This implies strong growth of the well-known renewable energy sources (RES) such as volatile wind & solar PV. An intensive debate is ongoing between the ones seeing an all-electric future and the ones promoting a technology mix like what we have today. With electric vehicles for passenger cars and trucks, electrification is supporting a new sector of energy consum-ers that was dominated by fuels until now. With the strong growth forecast for heat pumps electrification is also growing in the heating sector. But there is the big chal-lenge with the imbalance of volatile RES supply and electricity demand, which can-not be balanced with demand side man-agement and large battery energy storage alone.Energy storage is one of the big challenges within the energy transition. Multiple tech-

nologies exist that can manage the storage of relatively small amount of energy over a short period of time, but technologies that have large storage capacities and can store energy over a long period of time providing seasonal storage are also required (F i g -u r e 1 ). Currently the production of green hydrogen from RES is the most promising solution for large (TWh capacity) and sea-sonal renewable energy storage. Energy stored as hydrogen directly or hydrogen-based fuels such as synthetic methane, green methanol, ammonia or other syn-thetic fuels are the options on the table.

Maintaining a stable and steady energy supply that is mainly based on volatile RES requires a flexible and dispatchable backup solution. Battery energy storage solutions will be available but can only serve rela-tively small capacities and provide only hourly storage. Backup solutions based on fuels can provide large energy storage and especially for longer periods of time. Such fuels which will become 100 % renewable fuels over time, can be used in all kinds of established and mature technologies for centralized and distributed power genera-tion, such as combined heat and power (CHP), in the transport sector, the heating sector and industry. For power generation,

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P2G – CH4AmmoniaMethanol

Fig. 1. Energy storage options capacity vs. duration (© Innio Jenbacher).

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Decarbonizing distributed power solutions VGB PowerTech 12 l 2020

we call solutions based on renewable fuels dispatchable renewable energy sources (dRES), because they are available when needed and run on renewable fuels – an ideal complement to the volatile renewa-bles wind and solar PV.

Natural gas is the fuel of choice for decar-bonization. Switching from coal to gas al-lows to reduce carbon emissions by ~50 % and sometime even more if old coal power plants with low efficiency running on low rank coal are replaced (F i g u r e 2 ). Re-placing a liquid fuel power plant with the same electrical efficiency results in a 25 % carbon emission reduction, and at the same time polluting emissions can be re-duced by about 90 %. Fuel utilization of natural gas can be maximized by running the gas power plants as CHP, achieving 90 % and more total efficiency and reduc-ing carbon emissions by another ~33 % compared to the separate production of power from the same engine and produc-tion of heat from a gas boiler. By operat-ing a gas engine plant in CHP mode, spe-cific carbon emissions can be reduced to ~230 g CO2/kWh, coming very close to the carbon fuel content of natural gas with 202 g CO2/kWh. However, natural gas re-mains to be a fossil fuel.

F i g u r e 2 shows the decarbonization op-tions from the viewpoint of a gas engine solution provider with a focus on CHP and distributed power. A further reduction be-low 230 g/kWh of carbon dioxide emis-sions is only possible with the decarboniza-tion of the fuel that is used. Biogas or biom-ethane – considered to be a carbon neutral fuel according the IPCC report 2006 [1] – are well known renewable fuels for distrib-uted power generation. Another emerging fuel is hydrogen. Like electricity, hydrogen is an energy carrier and not a natural re-source. It is a fuel that is carbon free and can be used as a base product for synthetic fuels that are either carbon based (synthet-ic gas or methanol) or carbon free (like am-monia). Methanol and ammonia are chem-ical products that are widely used in the chemical industry but are considered as new fuels for internal combustion engines. When hydrogen is produced through the electrolysis of water and electricity stem-ming from renewable sources, it is called renewable hydrogen (green H2). When hy-drogen is produced with steam methane reforming, and with carbon capture and storage (CCS), it is called fossil-based hy-drogen with carbon capture (blue H2).

Solar PV is the most promising distributed RES that will be widely installed in the near and longer term. Battery storage can be used for shifting power from peak pro-duction to off-peak production times and increase the time with renewable power supply. For longer storage times, central-ized and distributed power running on re-newable fuels is a more reliable and a more sustainable solution, underlined by many

studies [9]. It can provide unlimited power supply and ideally produce heat or cold as CHP or CCHP solution. Highly flexible op-eration is still possible with CHP solutions when adding a heat storage system that de-couples electricity and heat supply. Heat storages combined with a gas engines CHP plant are typically built for hours or days of heat storage. It can be applied for smaller gas engines CHP plants as well as for larger plants like for the 190 MW Kiel CHP power plant in Germany, always with the same ef-ficiency, fuel utilization and highly operat-ing flexibility [2].

Gas Engines for Hydrogen Applications

Long-time experience with high H2 fuels for various applications.F i g u r e 3 shows three selected examples out of numerous Jenbacher engines run-ning on high hydrogen fuels which have been installed over the last 30 years total-ling an installed capacity of more than 200 MW. Fuels such as coke oven gas with a hydrogen content of up to 70 %(v), spe-

cial off gases from a chemical process with very low heating value or a synthetic gas from biomass gasification are used in Jen-bacher gas engines to generate power and heat. Typically, those gaseous fuels are available at low pressure and therefore ide-ally suited for the use in gas engines, be-cause the required fuel gas pressure is only ~100 mbar(g). All those fuels have a rela-tive constant fuel composition that does not change over time and therefore the rate of change (RoC) is low and a plug flow is not seen.

Hydrogen availability for gas engine solutionsINNIO Jenbacher classifies hydrogen appli-cations in 3 categories (F i g u r e 4 ):

– A Hydrogen that is a composition in the natural gas

– B Hydrogen that is locally admixed to the gas engines’ fuel

– C Pure hydrogen applicationsIt is important to understand the availabil-ity of hydrogen. In the natural gas network hydrogen can be available a few hours in the year, continuously but fluctuating, or

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Fig. 2. Decarbonization with fuels, technologies and their applications (© Innio Jenbacher).

Coke gas (Profusa)COD 1995

Process gas (Krems)COD 1996

Syngas (Mutsu)COD 2003

H2: ~50-70 Vol%CH4: ~20-25 Vol%LHV: ~5 kWh/m3

H2: ~15-17 Vol%CH4: ~1.5 Vol%LHV: ~0.5 kWh/m3

H2: ~30-40 Vol%CH: ~25-30 Vol%LHV: ~2.5 kWh/m3

Commercial Operation(more than 200 MW installed capacity)

Fig. 3. Project experience with high hydrogen fuels for Jenbacher gas engines (© Innio Jenbacher).

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continuously with constant amount. Ad-mixing hydrogen locally at the gas engines’ fuel allows to control the amount of hydro-gen that is mixed with natural gas, but again the hydrogen may be available a few hours per year, seasonally or continuously. The pure hydrogen gas engine can run only when hydrogen is available.

A Natural gas with high hydrogen content

Impact of hydrogen in natural gas pipeline systemsWith biogas upgraded to biomethane achieving pipeline gas quality standards as

the most common renewable gas currently used for greening the gas supplied to end customers, the gas industry is already pre-paring for a 100 % carbon neutral / carbon free future by 2050 [3]. But also hydrogen admixing to natural gas in the transmission and distribution networks is anticipated in parallel to the development of an inde-pendent hydrogen infrastructure. Especial-ly when hydrogen is mixed to natural gas in the distribution network system, many gas consumers are affected with fluctuating fuel properties as the physical composition of the gas is changing.The aim of adding hydrogen to the natural gas network is to decarbonize natural gas

and use the existing gas infrastructure for transport and storage. Studies show that up to 20 or 30 %(v) of hydrogen can be added to the existing natural gas transmis-sion and distribution system. 20 / 30 %(v) of hydrogen in the natural gas results in a decarbonization of only 7 / 11 %, because hydrogen has a volumetric heating value of less than 30 % compared to natural gas (F i g u r e 5 ). With 20 %(v) hydrogen the Wobbe Index (WI) of the gas is going down by 5 to 6 % (F i g u r e 6 ) and the Methane Number (MN) is going down by ~13 points (F i g u r e 6 ). If permanent, a constant switch from zero to a certain percentage of hydrogen could be done, all end users could adjust their appliances, turbines, gas engines, boilers, etc. accord-ingly. The real challenge is a very likely dis-continuous hydrogen injection to the natu-ral gas grid. Therefore, a stable and con-stant mixture of natural gas and hydrogen should be ensured by gas grid operators to avoid plug flows and inhomo-geneous mixtures. A varying hydrogen content in the natural gas results in a “wide Wobbe” gas with wide ranges of heating value and MN.

Gas engine solution for hydrogen in natural gas pipeline systemsAdding hydrogen to the natural gas net-work changes the physical composition of the gas, but not so when admixing biome-thane or synthetic methane to natural gas. The MN describing the resistance of fuel gases to engine knock is the most impor-tant metric for gas engine power plants. Figure 6 shows how the MN changes with higher hydrogen content in the natural gas up to 30 %(v). Important is also the base gas composition. A base gas with a high MN shows more points reduction in MN with a higher hydrogen content, but still it ends up at a higher MN than a base gas with a lower MN.When comparing the 2 charts for WI and MN, one can see that the lines with differ-ent gas compositions appear in reverse or-der. The natural gas with the highest WI has the lowest MN, and the gas with the lowest WI has the highest MN. But both WI

A

H2 in natural gas pipeline

B

H2 local admixing

C

Pure H2

Conventional NG+H2 fuel mixture boosted system

H2 fuel injection system

Fig. 4. Gas engine solutions depending on H2 availability (© Innio Jenbacher).

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Fig. 5. Hydrogen effect on decarbonization of natural gas (© Innio Jenbacher).

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Fig. 6. Wobbe Index (WI) and Methane Number (MN) change depending on H2 content in pipeline gas (© Innio Jenbacher).

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and MN are decreasing with higher hydro-gen content up to 30 %(v).

Smaller amounts of hydrogen in the natural gas with less than 5 %(v) change the MN only slightly and that is typically within the tolerance of the gas engine design. Such an engine can operate with a design optimized for the base natural gas composition. A higher amount of hydrogen in the natural gas typically requires a broadband product designed for a lower MN. Such an engine can tolerate both higher and lower MN gas and maintain constant output, but with lower electrical efficiency.

There is a significant difference whether a reliable signal about the current hydrogen content in the natural gas is available or not. If a reliable signal about the hydrogen con-tent is available to the gas engine, the con-trol of the engine can automatically adjust accordingly and the gas engine can run on full output at high hydrogen content, while meeting emission requirements and run reli-ably. If there is no signal about the hydrogen content available to the gas engine control, the control system will go to a save opera-tion mode when entering the knocking limit with the consequence of reducing output.

An engine that operates with high hydro-gen in the pipeline gas (F i g u r e 7 ) and has a Jenbacher LeanoxPlus control system installed can keep NOx emissions within the limits, but older engines would need an up-grade to LeanoxPlus. For reliable operation of such an engine a signal about the hydro-gen content would still be required, espe-cially when the hydrogen content changes in a wide range. Retrofit options are avail-

able including software changes to upgrade the engine controls and hardware changes to convert the engine to a broadband prod-uct. Retrofit options depend on the hydro-gen content in natural gas, the availability of the hydrogen in the natural gas and whether a signal on hydrogen content is available or not. Above certain limits the plant’s safety concept needs to be reviewed and adapted accordingly.INNIO Jenbacher recommends having a reliable hydrogen signal available if the hydrogen content in natural gas is >5 %(v).

Ta b l e 1 shows the relevant fuel gas re-quirements for Jenbacher gas engines. To ensure reliable operation of gas engines, it is recommended to keep the fluctuation of the LHV and the rate of change (RoC) for the MN as well as for the H2 content within certain limits.

B Local admixing of hydrogen to natural gas fuelAdmixing hydrogen locally at the gas en-gine allows control of the amount of hydro-gen that is mixed with natural gas and the hydrogen content is always known to the engine control system. That makes this gas engine configuration easier to design and operate (F i g u r e 8 ). INNIO Jenbacher distinguishes between 2 solutions.B-1: Premixed gas engines for mixing lo-cally up to ~60 %(v) hydrogen to pipeline natural gas. This allows to use a conven-tional fuel system with a single fuel-air mixing pre-turbocharger. The fuel supply system including the turbocharger design is adjusted according the maximum amount and the availability of admixing hydrogen. The engine can still run at 100 % natural gas achieving full output but will reduce output at higher hydrogen admix-ing depending on the base gas and engine version. The design of the engine can be optimized for 100 % natural gas operation or for the operation with high hydrogen ad-mixing.B-2: A dual gas engine is required if the engine should be capable of running on 100 % natural gas as well as 100 % hydro-gen. In this case two fuel supply systems on the engine are required. A conventional fuel system with a fuel-air mixing pre-tur-bocharger for natural gas operation and a separate fuel injection system for hydrogen operation. The engine performance can be optimized for 100 % natural gas operation or for 100 % hydrogen operation.

NG+H2

Fig. 7. Gas engine running with pipeline gas including hydrogen content (© Innio Jenbacher).

Tab. 1. Relevant fuel gas requirements for Jenbacher gas engines.

Characteristic Limits Unit

LHV Fluctuation ≤ 4 %/min

MN RoC ≤ 10 MN/min

H2 content in NG RoC ≤ 4 Vol %/min

100 % H2 H2 purity not relevant % H2

controlled admixingH2 NG

Fig. 8. Gas engine running with local admixing of up to 60 %(v) or 100 % hydrogen (© Innio Jenbacher).

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Ta b l e 2 shows some examples where lo-cal admixing of high hydrogen content has been demonstrated on Jenbacher gas en-gines. SINFONIA and H2ORIZON are two EU Horizon 2020 funded projects. Ando Hasama is a demonstration project in Ja-pan where local hydrogen admixing was demonstrated successfully beginning 2020. The project Othmarschen is HanseWerk Natur’s project to demonstrate the first MW scale gas engine that can run on both 100 % natural gas as well as 100 % hydrogen. HanseWerk Natur is an E.ON company that operates several distributed gas engine CHP plants in the Hamburg area – an area that should become a hydrogen role model in Germany.Hychico (F i g u r e 9 ) is a demonstration project in Argentina built in 2008. A 6.3 MW wind farm was installed in an oil and gas exploration area. This wind farm is

demonstrating a very high capacity factor above 50 %, and the region is one with the biggest onshore wind potentials globally. Next to the wind farm 2 electrolyser units with a total capacity of 0.8 MW have been installed to demonstrate power-to-gas and hydrogen underground storage. One of many gas engines in the region providing distributed power to run the oil and gas wells is used to re-convert the hydrogen to power. This is done by admixing up to 42 %(v) hydrogen to natural gas locally at the engine. Hydrogen stored in a local empty gas field needs no additional treat-ment to increase purity before it is admixed to natural gas. The control system of the J420 gas engine uses the hydrogen signal to ensure smooth engine operation with varying natural gas / hydrogen mixtures. Between 0 and 27 %(v) hydrogen the en-gine runs at full output of 1,415 kW, and

between 27 and 42 %(v) of hydrogen the engine output is gradually reducing to ~83 % of nominal output. Meanwhile, the J420 gas engine which started operation in 2008 has accumulated more than 70,000 operating hours, It was inspected during the major overhaul at 60,000 oh and found in excellent condition.F i g u r e 10 shows how important it can be to have a reliable hydrogen signal available to the gas engine control system. The SIN-FONIA J612 gas engine was designed for 250 mg/Nm3@5 %O2 NOx emission when running on 100 % natural gas (MN ~90) and had no closed loop NOx control as the LeanoxPlus offers today. When running this engine with 30 %(v) hydrogen admixing and without a signal to the engine control system, the NOx emission would increase by ~20 % and would be well outside required emission limits. When running this engine with 30 %(v) hydrogen admixing and with a hydrogen signal to the engine control sys-tem, the NOx emission could be reduced by ~50 % below the required emission limits.Newer gas engines already have a Lea- noxPlus installed that keeps NOx levels with-in required limits even when hydrogen in the fuel changes the combustion character-istics. This advanced control system is also available as a retrofit for the installed base. Retrofit options for hardware changes are also available if this is required due to high-er hydrogen content admixed to natural gas and changing the engine’s optimal op-erating point. For a dual gas engine that can run on 100 % natural gas as well as 100 % hydrogen more hardware changes are required, because this engine requires a dual gas fuel system. Retrofit options de-pend on the maximum admixing hydrogen content, the availability of the hydrogen and the operation for which the gas engine should be optimized.

C 100 % hydrogen utilizationOperating a distributed power asset on 100 % hydrogen is the long-term vision, but some gas engines for peaking and CHP could be installed to run on hydrogen al-ready in the near term as hydrogen clusters emerge and transfer away from fossil fuel completely. If hydrogen is the fuel of choice and no other carbon neutral or carbon free fuel for backup is available, the gas engine can be designed for 100 % hydrogen opera-tion with a single fuel system (F i g u r e 11 ). INNIO Jenbacher successfully ran tests with a small 160 kW gas engine on 100 % hydrogen at Husum, Germany 20 years ago.INNIO Jenabcher is participating in the Ho-rizon 2020 project “HyMethShip” (F i g u r e 1 2 ). The aim of this project is to develop and demonstrate a marine concept that runs on renewable fuel with zero carbon emissions. Methanol produced from green electricity is used as a liquid energy carrier on the ship. On board a small methanol re-

Tab. 2. Example projects with high hydrogen local admixing.

Project Country Engine type Configuration

SINFONIA, Bozen Italy J612 up to 30 %(v) H2 locally admixing

HYCHICO Argentina J420 up to 42 %(v) H2 locally admixing

H2ORIZON, DLR Germany J312 up to 60 %(v) H2 locally admixing

Ando Hasama Japan J312 up to 60 %(v) H2 locally admixing

Othmarschen, E.ON Germany J416 100 % NG and 100 % H2

Fig. 9. J420 hydrogen demonstration project at Hychico, Argentina (© Innio Jenbacher).

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forming plant is separating and capturing the CO2 before the hydrogen is used to run the gas engine propulsion system. The CO2 is used in a closed circle for methanol pro-duction on land and the ship is operating carbon emission free. The whole “off-shore” system, including a 1 MW Jenbacher gas engine is demonstrated by the LEC GmbH at the Graz University of Technology.HyMethShip [4] is an example to demon-strate hydrogen gas engine applications. The same engine can be used for any other applications such as distributed power gen-eration, CHP, balancing power or peak shav-ing – all applications where engines run to-day on natural gas or other fossil fuels.Retrofit options for converting a natural gas engine to a hydrogen engine will be available soon for dedicated products. It requires software changes for the engine controls together with some hardware changes. While such a gas engine is opti-mized for hydrogen operation, it is still im-portant to understand the availability of hydrogen, the application and the operat-ing profile of the gas engine.

Gas Engines future fuels and applications

While natural gas is the most commonly used fuel for gas engines, 6,000 Jenbacher gas engines are already running on non-natural gas in Europe. The main non-natu-ral gas application for Jenbacher gas en-gines is raw biogas, but also sewage gas, landfill gas, flare gas, or a wide range of process gases are used since many years. Biomethane could replace natural gas to a certain extent while having the same phys-ical properties. Synthetic methane pro-duced from hydrogen (preferably green hydrogen) is also an ideal replacement for fossil natural gas.

Hydrogen as a fuel for gas engines is a promising solution, because the gas engine technology is available and proven for a wide range of gaseous fuels and there is no need for new technology invention, only modifications of some parts on the engine. However, to achieve high power density, high efficiency and reliable operation with hydrogen as the main fuel for gas engines needs more experience and further devel-opment.Methanol and Ammonia (NH3) are two chemical products that are widely used in the chemical industry and are currently considered to play a bigger role in a 100 % renewable energy system. Methanol could become an energy carrier as demonstrated in the R&D project HyMethShip, or a future carbon neutral fuel when produced from green hydrogen. Ammonia has a very high energy density and is therefore considered as a liquid energy carrier, alternatively Am-monia is considered as a carbon free fuel. Both, methanol and ammonia, can be used

H2-signal not available H2-signal available

NO

x

Fig. 10. SINFONIA gas engine running with local admixing of up to 30 %(v) hydrogen.

H2

Fig. 11. MW scale gas engine for 100 % hydrogen operation (© Innio Jenbacher).

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Fig. 12. Emission free ship propulsion with a hydrogen gas engine (© LEC GmbH).

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as fuel for internal combustion engines and their various applications (F i g u r e 1 3 ).

Outlook on emissions:CO2 emissions are going down in a non-line-ar way when we look at a hydrogen vol-ume % content, because there is a significant difference in lower heating value per Nm3 between natural gas and hydrogen of a fac-tor of 3.4. Therefore, it requires more than 75 %(v) hydrogen to reduce carbon emis-sions by 50 % (blue curve). NOx emissions are expected to decrease as well, because of switching to a leaner combustion process (green curve). However, if hydrogen is pro-vided in an uncontrolled way and the engine is not equipped with the latest LeanoxPlus control technology, NOx emissions will go up and can quickly exceed emission limits (red curve). In order to ensure a safe and reliable gas engine operation a signal about the hy-drogen content would still be required, espe-cially when the hydrogen content changes in a wide range (F i g u r e 14 ).

Conclusion

Although the energy transition often is con-sidered to be expensive, in many places re-newable power generation from solar and wind already is the most economic power source. While at the end a more or less 100 % renewable world might be very af-fordable, the challenge lies in the transition period. During the time until renewables can take over, a parallel supply with gradu-ally phasing out fossil fuels is required for reliable power and heat supply. Sometimes but not always with parallel infrastructure.Renewable fuels allow for the use of estab-lished and widely available infrastructure for transport and distribution, storage and retail selling. Changes and adaptions are required to switch that infrastructure from today’s fossil-based fuels to renewable fu-els but are available and are being imple-mented already. Current power generation technologies can be used and allow a flex-ible transition from the use of fossil fuels to

renewable fuels when they become availa-ble at different places.The most cost effective and fastest solution achieving the energy transition targets and become carbon neutral is the utilization of existing infrastructure with required adap-tations to allow changing the fuel. Stranded investments should be avoided as much as possible, and this is achievable by a smart design of our products today allowing retro-fits for an easy transition to renewable fuels.The plans for the energy transition should be solid and credible with implementation plans and milestones in order to allow achieving it in an affordable way.INNIO, Jenbacher and Leanox are trade-marks.

References:[1] 2006 IPCC Guidelines for National Green-

house Gas Inventories, for Stationary Com-bustion V2 2 CO2; Darío R. Gómez et.al., 2006.

[2] Gas engines – Combining efficiency and flex-ibility with CHP; Dr. Klaus Payrhuber, Dipl. Ing. Martin Schneider, Dipl. Ing. Herbert Schaumberger, Martin Thur, VGB Power Tech 2017.

[3] Gas for Climate – Gas Decarbonization Pathways 2020-2050; Guidehouse, April 2020.

[4] HyMethShip; www.hymethship.com, LEC Graz.

[5] Wasserstoff für Gasmotoren – Kraftstoff der Zukunft; Dr. Stephan Laiminger, Dr. Mi-chael Url, Dr. Klaus Payrhuber, Dipl. Ing. Martin Schneider, MTZ, May 2020.

[6] Hydrogen as Future Fuel for Gas Engines; Dr. Stephan Laiminger, Dr. Michael Url, Dr. Klaus Payrhuber, Dipl. Ing. Martin Schnei-der, 29. CIMAC Congress, Vancouver, 2019.

[7] EU Hydrogen Strategy; 2020.[8] German Hydrogen Strategy; 2020.[9] Klimaneutrales Deutschland; Agora Ener-

giewende, 2020.[10] 2030 Peak Power Demand in North-West

Europe; Engie Report, September 2020. l

ErneuerbareEnergieerzeugung

EnergieumwandlungP2G & G2P Energiespeicherung Wasserstoff-Anwendungen

MethanolCH3OH

E-FuelsCxHy

AmmoniakNH3

GasnetzErdgas

BiomethanCH4

Industrie & O&G

Stahlindustrie

H2Fahrzeuge

Biogas CH4 + CO2

Elektrolyse

Biogas

Fig. 13. Gas engine applications in a carbon neutral / carbon free future (© Innio Jenbacher).

H2 in Vol-%

Rel.

CO2

cont

ent o

f nat

. gas

in %

100

90

80

70

60

50

40

30

20

10

0

CO2 and NOx Emissions with NG and H2NG in Vol-%

NO

x Em

issio

ns in

%

0 10 20 30 40 50 60 70 80 90 100

Fig. 14. Gas engine emissions with NG and H2 mixtures ( CO2, NOx, NOx without closed loop control (LeanoxPlus)).

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The electricity sector at a crossroads The role of renewables energy in Europe

Power market, technologies and acceptance

Dynamic process simulation as an engineering tool

European Generation Mix Flexibility and Storage

1/2

2012




The electricity sector

at a crossroads

The role of renewables energy

in Europe

Power market, technologies and acceptance

Dynamic process simulation as an engineering tool

European Generation Mix

Flexibility and Storage

1/2

2012




The electricity sector

at a crossroads

The role of

renewables energy

in Europe

Power market,

technologies and

acceptance

Dynamic process

simulation as an

engineering tool

European

Generation Mix

Flexibility and

Storage

1/2

2012

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