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英译汉：This paper presents the results of simulated case studies, analyzing the effects of a novel price-based control system in a 1.5 GW offshore wind-hydrogen facility in Norway. The novel control system was com bined with a polynomial regression model that estimates the wind farm capacity factor based on wind speed input and a hydrogen production model based on a previously developed model (Egeland-Eriksen et al., 2023). Real-world wind speed and energy production data from a 2.3 MW FOWT were used to train the 12-degree polynomial regression model. The regression model was then combined with the hydrogen production model and the novel control system, as well as 10 years (2013-2022) of real-world data of wind speeds and electricity prices from a location in Norway, close to the planned location of the 1.5 GW Utsira Nord (Utsira Nord, 2024) floating offshore wind farm. We simulated 11 different case studies of a 1.5 GW wind-hydrogen system, using both current and future (2050) scenarios. The results indicate that large-scale hydrogen production via PEM electrolysis with electricity from an offshore wind farm could become economically and technically viable if a price-based control system is used to decide when the wind power is used to produce hydrogen and when it is sold directly to the electricity grid. The novel control system developed in this study resulted in a LCOH of 6.04 $/kg H2 in the base case (current technology and costs), which is within current LCOH estimates for green hydrogen (2.5-6.8 $/kg H2 in (Vickers et al., 2020) and 3.2-7.7 $/kg H2 in (Global average levelised cost of hydrogen production by energy source and technology, 2019)). This was a 32% reduction in LCOH compared to the same case without the control system. However, this is still more than three times as high as the LCOH of grey hydrogen, currently estimated to be in the range 0.7-1.6 $/kg H2 (Global average levelised cost of hydrogen production by energy source and technology, 2019). When using technology improvements and cost reductions forecast for 2050, the resulting LCOH in the most optimistic cases were 0.96 $/kg H2 when only electricity from offshore wind was used and 0.82 $/kg H2 when the electrolyzer was allowed to use grid electricity. The latter will not qualify as green hydrogen though, unless the electricity grid is based on 100% renewable energy. The novel control system developed in this study had a positive effect in all simulation cases and reduced the LCOH by 10-46% compared to the equivalent cases without the control system. These results show that a control system of the type proposed in this study will be a crucial factor to make wind-hydrogen systems econom ically viable. Finally, the simulation case where the electrolyzer was located offshore in a 1.5 GW off-grid wind farm resulted in a LCOH of 4.96 $/kg H2, which indicates that it will be challenging for off-grid offshore wind-hydrogen systems to compete with onshore hydrogen production systems. To increase the realism of the model, several aspects can be sug gested. These include integration of even more realistic dynamics of PEM electrolyzer usage (ramp-up/cold start-up time, energy usage for standby mode) and its degradation over its lifetime; consider dynamic process simulations of the compression, storage and transport of hydrogen (instead of using a constant per kg of hydrogen) and of the desalination of sea water for the off-grid offshore scenarios (instead of using a constant per kg of hydrogen). The accuracy of the proposed model will also benefit from the addition of power electronics, and the price-based control system could benefit from access to a dynamic selling price of hydrogen instead of using a constant value. Furthermore, an analysis to simulate the effect that large-scale green hydrogen production with price-based control systems will have on the electricity price (feedback effect) will be useful toward the realization of real-world wind-hydrogen systems at the scale necessary to propel a sustainable transition.

The significance of green, low-emission hydrogen energy in the process of decarbonization and the advancement of a global zero-carbon energy system has been recognized [1]. The United Nations has voiced support for clean hydrogen energy in achieving global net-zero emissions [2]. Currently, hydrogen is primarily obtained from carbon-intensive energy sources, such as steam methane reforming (SMR) and coal gasification, which are referred to as gray hydrogen and black hydrogen [3], respectively. Low-carbon hydrogen production technologies, such as water electrolysis by renewable or low-carbon electricity, offer an alternative and improved solution for decarbonizing energy systems [4,5]. According to the International Energy Agency (IEA) report, low-carbon hydrogen is projected to account for 70% of global hydrogen sources by 2030, with almost all sources being low-carbon by 2050 [6]. Currently, national policies on hydrogen energy, such as those of China [7], recognize hydrogen production from renewable electricity generators as a key avenue for future hydrogen production [8,9].

Hydrogen (氢)is the lightest element(元素)in the world,and there's more hydrogen in the world than you think -for example,water has hydrogen elements.Some think it could be a big deal in the energy industry.It burns easily and can power things that need a lot of heat, like furnaces(熔炉).Unlike wood or fossilfuels(化石燃料),it doesn't make CO,that warms the climate (气候). How can oe use hydrogen? Hydrogen has many uses,from making plastics to purifying(炼制)oil.When used as energy,it burns cleanly and can replace fossil fuels,reducing greenhouse gas emissions(温室气体排放). Some companies,like Cleveland- Cliffs in the US,started to use hydrogen as a fuel source,with plans to mix it with methane(甲烷). In this way,the fuel can burn greenhouse gas and leave no pollution.Hydrogen can also make electricity through chemical reactions(化学反应) between hydrogen and oaygen(氧气).The only byproduct is water - it's a very clean resource(资源). Using hydrogen for energy is hardly a new idea.According to a study released in February 2023, there have been about 56,000 hydrogen-powered passenger vehicles(车辆)on the road. Why isn't everyone usingit? Hydrogen comes in different forms,and its cleanliness depends on how it's made.Although hydrogen is naturally found in the universe,the one we need for energy is not common.Companies have to get hydrogen from other sources,mainly from fossil fuels, which often leads to pollution. However,the cleanest,“greenest” way to make hydrogen is possible, but very expensive.People aren't ready to pay a lot of moneyfor this.

英译汉：The aim of this study is to assess the economic potentials of power and hydrogen generation via solar and wind energy resources at locations in Northern Germany and California, both of these (geographical) regions being pioneers in terms of a sustainable energy transition. Based on extensive research and electrolyzer manufacturer interviews, green hydrogen generation plants are modeled in a MATLAB® environment. All relevant inputs and outputs of the systems studied (wind power plants, photovoltaic power plants, and polymer electrolyte membrane electrolyzers, among others) are considered for different locations and framework conditions. In contrast to the existing literature, special attention is paid to the part-load behavior of electrolysis systems, which becomes particularly relevant in their interplay with volatile renewables. Metrics such as the levelized costs of electricity (LCOE) of the wind and photovoltaic power plants and the resulting levelized costs of hydrogen (LCOHy) are determined. With the help of the developed model, dimensioning of a whole system's components can be determined for different locations. A case study is conducted for a Northern German site and another one for a site in the Californian Mojave Desert. Both the optimal dimensioning of the renewable energy plants and the ratio of installed wind and photovoltaic power plant capacity are strongly location-dependent. In Northern Germany, for example, lower LCOHy can be generated at higher wind power plant capacity shares and, in the Mojave Desert, be produced at higher photovoltaic power plant capacity shares. In general, with larger plants and correspondingly larger polymer electrolyte membrane electrolyzers, LCOHy are lower due to scaling effects. Following this dimensioning recommendation, the LCOHy vary between 4.5 €/kg and 5.2 €/kg in the Northern German case study and between 4.6 US$/kg and 5.3 US$/kg in the Californian one. With costs of 1–2 €/kg, gray hydrogen is still economically superior.

The cost of hydrogen production through PEMWE in China was calculated and forecasted via the collaboration of bottom-up cost analysis, scenario analysis, learning curve method and H2A model. (1) The total cost of hydrogen production in current Scenario 1 is calculated to be 7.26 $/kg, i.e., ~48.6 ¥/kg, with the capital cost of 4450 $/kW for the electrolyzer system. The capital cost and electricity cost account for 47.6% and 34.7% of the total cost, respectively. (2) In the future Scenario 3, the different learning rates on different components of electrolyzer are described to predict the initial capital cost of the electrolyzer system in 2040. Meanwhile, the operating parameters of electrolyzer including voltage and current density are improved and the production scale of a single electrolyzer is magnified. Therefore, the capital cost of electrolyzer system reduces to 812 $/kW and the calculated cost of hydrogen production reduces to 2.60 $/kg. At this moment, the electricity cost with ratio of 56.4% will become the predominant affecting factor. (3) The capital cost, electricity cost, electrolyzer performance, and the production scale of a single electrolyzer contribute to the cost reduction of 71.03%, 21.27%, 6.22% and 1.50% respectively, leading to a reduction of the initial cost of 7.26 $/kg H2 in Scenario 1 to 2.60 $/kg H2 in Scenario 3. (4) When the capital cost is reduced by 10% and 20%, PEMWE hydrogen production cost is reduced from 7.26 $/kg to 6.81 and 6.36 $/kg, respectively. It indicates that the current hydrogen production cost has the declining potential, considering there should be a profit margin of 10–20% for the commercial quotation from PEM electrolyzer manufacturer. (5) The fluctuation of 10% in the electricity cost presents a cost range of hydrogen production between 7.00 $/kg and 7.52 $/kg for Scenario 1 and between 2.45 $/kg and 2.75 $/kg for Scenario 3. (6) The hydrogen production cost of 2.60 $/kg in Scenario 3 will show the advantage when the carbon tax of 78.82 $/t CO2 eq. for coal gasification and 107.48 $/t CO2 eq. for SMR are imposed.