In order to keep the Paris Agreement's goal of limiting global warming to well below 2°C, greenhouse gas emissions should be reduced. However, larger measures need to be implemented as it has been established that today's measures will not be enough. The Port of Gävle has plans to install a water electrolyser for hydrogen production of either Proton Exchange Membrane (PEM) or Alkaline Water Electrolysis(AWE). The size of the electrolyser will be approximately 10 MW and will have the capacity to produce 2,000 tons of fossil-free hydrogen per year that might supply 100 heavy trucks. However, it is currently cheaper with fossil hydrogen production. Therefore, an article review is conducted containing a calculation part where the purpose is to investigate the amount of by-products produced and whether they can be sold in other areas of use to make renewable hydrogen more economically competitive. Information for the study has been retrieved from databases, search engines, companies, authorities and individuals deemed relevant to the study. The by-products from the 10 MW electrolyser in the Port of Gävle have been compared with 1,5 MW and 17 MW electrolysers, then a sensitivity analysis has also beenperformed on the 10 MW electrolysers. The potentially generated heat depends on the type of electrolyser where AWE generates 77 MWh of residual heat per day and PEM potentially generates 67 MWh of residual heat per day. Furthermore, AWE needs 64 kWh of electricity to produce 1 kg of hydrogen while PEM needs 66,5 kWh of electricity per kg of hydrogen produced. Revenues from residual heat sales for AWE were estimated annually to approximately 7 million SEK and for PEM approximately 6 million SEK. For electrolysis-produced oxygen to compete with cryogenic oxygen, the price should not exceed 108 SEK/tonne. For the 10 MW electrolyser, oxygen sales are estimated to generate approximately 1,1 million SEK annually for both AWE and PEM. Total income for AWE will annually be just over 8,1 million SEK and 7.1million SEK annually for PEM. The AWE process is then preferable as it is more economically sustainable as the income from the by-products is 12% higher than PEM due to higher production of oxygen and greater generation of residual heat. / För att hålla Parisavtalets mål att begränsa den globala uppvärmningen till väl under 2°C bör utsläppen av växthusgaser minska. Däremot behöver större åtgärder genomföras då det har konstaterats att dagens åtgärder inte kommer att räcka. Gävle hamn har planer på att installera en vattenelektrolysör för vätgasproduktion av antingen Protonutbytesmembran (PEM) eller Alkalisk vattenelektrolys (AWE). Storleken på elektrolysören kommer vara ungefär 10 MW och har kapaciteten att producera 2000 ton fossilfri vätgas per år som kan försörja 100 tunga lastbilar. Dock är det i dagsläget billigare med fossil vätgasproduktion. Därför genomförs en litteraturstudie innehållande en beräkningsdel. Där syftet är att undersöka mängden biprodukter som produceras samt om de kan säljas inom andra områden för att göra förnyelsebar vätgas mer ekonomiskt konkurrenskraftig. Information för studien har hämtats från databaser, sökmotorer, företag, myndigheter och enskilda personer som ansetts relevanta för studien. Biprodukterna från 10 MW elektrolysören i Gävle hamn har jämförts med 1,5 MW och 17 MW elektrolysörer, sedan har även en känslighetsanalys utförts på elektrolysörerna. Potentialen att generera värme beror på typen av elektrolysör där AWE genererar 77 MWh restvärme per dygn och PEM genererar potentiellt 67 MWh restvärme per dygn. Vidare behöver AWE 64 kWh el för att producera 1 kg vätgas medan PEM behöver 66,5 kWh el per producerat kg vätgas. Intäkterna från restvärmeförsäljningen för AWE beräknades årligen till ungefär 7mnSEK och för PEM ungefär 6 mnSEK. För att elektrolysframställd syrgas ska kunna konkurrera med kryogent framställd syrgas bör inte priset övergå 108 SEK/ton. För 10 MW elektrolysören beräknas syrgasförsäljningen kunna inbringa omkring 1,1 mnSEK årligen både för AWE och PEM. Totala inkomsten för AWE blir drygt 8,1 mnSEK/år och 7,1 mnSEK/år för PEM. AWE processen är att föredra då den är mer ekonomiskt hållbar då inkomsten från biprodukterna är 12% högre än PEM på grund av högre produktion av syrgas samt större generering av restvärme.

Hydrogen gas (H2), that is not produced from fossil oil or natural gas, is expected to become a cornerstone in the energy transition strategy in Europe. The recent years, technological and economic advances in the electrolyzer area, along with political and corporate support, have put H2 at the forefront of many countries’ climate change agenda. Consequently, green H2 is poised to play a large role in the coming energy transition to combat climate change. The possible advantages of integrating H2 production with a combined heat and power plant, or CHP, is investigated in this study. More precisely, the water electrolysis is carried out based on the purified flue gas condensate water and excess heat is recovered as district heating. A comparison of today’s three most common electrolyzer technologies was made, where Proton Exchange Membrane, or PEM, technology was chosen for this project, mainly for its high purity of H2 gas, robust construction, and the ability to run it as a fuel cell. Based on a mass and energy balance, a model including the integration of a PEM with a generic CHP plant was developed. The model was made modifiable, making it possible to change governing parameters, to be able to investigate different possible scenarios. Production flows, losses and other relevant data was calculated from the model. Operational data for the PEM electrolyzer were collected from several manufacturers where a mean value of the data was used as a base-case for the calculations. Based on literature and consulting experts, several assumptions were made, for example the selling price of H2 and the price for electricity. From the base-case were two cases made: a linear and non-linear case. The linear case uses the same input data each year for 20 years, while the non-linear case uses a changing input data each year for 20 years. Calculations were based on an electrolyzer size of 1,4 MW, where auxiliary equipment consumed additional 0,04 MW, resulting in a total energy consumption of 1,44 MW. An operational temperature of 80°C was assumed along with an operational pressure of 5 and 30 bar for the anode and cathode respectively. This resulted in an H2 production flow of 26 kg/h, a process water requirement of 0,2 m3/h, and a possible heat recovery amount of 0,34 MWh with a relevant temperature for the use in district heating. The study shows that the condensate-water at E.ON could provide for ~4000 hours of operation in the wintertime. To enable full operation all year around, a purchase of tap water would be necessary. The economical calculations resulted in an H2 production cost of 53 SEK/kg for the linear case and 58 SEK/kg for the non-linear case. The linear case showed a positive internal rate of return, or IRR, of 1,7%, while the non-linear case resulted in IRR < -25%. A sensitive analysis was made to examine governing parameters. The results of the sensitivity analysis showed that the largest driving variables, that significantly affect the IRR, are the price for electricity and the selling price for H2. The largest OPEX cost was found to be the price of electricity. The results showed that it is feasible to produce H2 at E.ON Örebro in a resource efficient way under certain circumstances, correlated to the electricity and H2 market. With a low electricity price and a selling price of ~50 SEK/kg for H2, good profitability is expected.  It is also clear that future work should focus the areas of O2 usage, infrastructure, and market investigation for a more definitive conclusion.

Vätgas kan framställas från förnybara energikällor genom vattenelektrolys med anjonbytande membran (AEMWE). AEMWE har vissa fördelar jämfört med traditionell alkalisk vattenelektrolys och elektrolysmed protonledande membran. Till exempel finns det möjlighet att använda alkalisk elektrolyt (även rent vatten) och billiga platinagruppsmetallfria katalysatorer tillsammans med ett anjonbytesmembran. Den största utmaningen med tekniken är att uppnå utmärkt och stabil prestanda för membran och elektroder. AemionTM anjonbytande membran (AEMs) av olika tjocklek, vattenupptag och kapacitet undersöktes i ett AEMWE system med 5 cm2 elektrodarea. Elektrokemisk prestanda hos dessa kommersiella AEM studerades med hjälp av porösa nickel elektroder. Bland de undersökta membranen visade AF2-HWP8-75-X stabil prestanda med en högfrekvent resistans (HFR) på 90 mΩ•cm2 och kunde nå en strömtäthet på 0,8 A/cm2 vid 2,38 V med 1 M KOH vid 60 ˚C.  AEMWE med AF2-HWP8-75-X och olika elektrodkombinationer undersöktes under samma driftsförhållanden. En elektrodkombination med Raney-Ni och NiFeO som katod respektive anod visade bäst prestanda under utvärderingen och gav en strömtäthet på 1,06 och 3,08 A/cm2 vid 2,00 respektive 2,32 V. KOH-lösningens temperatur och koncentration sänktes till 45 ˚C respektive 0,1 M för att undersöka effekten av driftsparametrar på flödescellens prestanda. Flödescellen uppvisade god stabilitet under de nya driftsförhållandena, men dess prestanda minskade avsevärt. Den nådde en strömtäthet på 0,8 A/cm2 vid 2,25 V. / Hydrogen can be produced from renewable energy sources using a novel anion exchange membrane water electrolysis (AEMWE) system. AEMWE has some benefits over the currently used state-of-the-art alkaline and proton exchange membrane water electrolysis systems. For instance, there is a possibility of using alkaline electrolytes (even pure water) and low-cost platinum-group-metal free catalysts together with an ion exchange membrane. However, the main challenge is that the AEMWE system should show excellent and stable performance, depending on the stability of the membrane and the electrodes. AemionTM anion exchange membranes (AEMs) of different thickness and water uptake capacity were investigated using a 5 cm2 AEMWE system. The electrochemical behaviour of these commercial AEMs was studied using nickel (Ni) felt electrodes. Among the investigated AEMs, the AF2-HWP8-75-X showed stable performance with a high frequency resistance (HFR) of 90 mΩ•cm2 and was able to reach a current density of 0.8 A/cm2 at 2.38 V using 1 M KOH at 60 ˚C.  AEMWE systems based on AF2-HWP8-75-X and different electrode combinations were examined under the same operating conditions. An electrode combination with Raney-Ni and NiFeO as cathode and anode, respectively, showed the best performance during the degradation test and provided a current density of 1.06 and 3.08 A/cm2 at 2.00 and 2.32 V, respectively. The operating temperature and concentration of the KOH solution were reduced to 45 ˚C and 0.1 M, respectively, to study the effect of operating parameters on the flow cell performance. The flow cell showed good stability under the new operating conditions, but its performance was reduced significantly. It reached a current density of 0.8 A/cm2 at 2.25 V.