Publications

Renewable energy technologies and resources particularly solar photovoltaic systems provide cost-effective and environmentally friendly solutions for meeting the demand for electricity. The design of such systems is a critical task as it has a significant impact on the overall cost of the system. In this paper a mixed-integer linear programming-based model is proposed for designing an integrated photovoltaic-hydrogen renewable energy system to minimize total life costs for one of Saudi Arabia’s most important fields a greenhouse farm. The aim of the proposed system is to determine the number of photovoltaic (PV) modules the amount of hydrogen accumulated over time and the number of hydrogen tanks. In addition binary decision variables are used to describe either-or decisions on hydrogen tank charging and discharging. To solve the developed model an exact approach embedded in the general algebraic modeling System (GAMS) software was utilized. The model was validated using a farm consisting of 20 greenhouses a worker-housing area and a water desalination station with hourly energy demand. The findings revealed that 1094 PV panels and 1554 hydrogen storage tanks are required to meet the farm’s load demand. In addition the results indicated that the annual energy cost is $228234 with a levelized cost of energy (LCOE) of 0.12 $/kWh. On the other hand the proposed model reduced the carbon dioxide emissions to 882 tons per year. These findings demonstrated the viability of integrating an electrolyzer fuel cell and hydrogen tank storage with a renewable energy system; nevertheless the cost of energy produced remains high due to the high capital cost. Moreover the findings indicated that hydrogen technology can be used as an energy storage solution when the production of renewable energy systems is variable as well as in other applications such as the industrial residential and transportation sectors. Furthermore the results revealed the feasibility of employing renewable energy as a source of energy for agricultural operations.

Electric scooters are used as alternative ways of transport because they easily make travel faster. However the batteries can take around 5 h to charge and have an autonomy of 30 km. With the presence of the hydrogen cell a hybrid system reduces the charging times and increases the autonomy of the vehicle by using two types of fuel. An increase of up to 80% in maximum distance and of 34% in operating times is obtained with a 1:10 scale prototype with the hydrogen cell; although more energy is withdrawn the combined fuel efficiency increases too. This suggests the cell that is used has the same behavior as some official reported vehicles which have a long range but low power. This allows concluding that use of the cell is functional for load tests and that the comparison factor obtained works as input for real-scale scooter prototypes to compete with the traditional electric scooters.

The Brazilian energy grid is considered as one of the cleanest in the world because it is composed of more than 80% of renewable energy sources. This work aimed to apply the levelized costs (LCOH) and environmental cost accounting techniques to demonstrate the feasibility of producing hydrogen (H2 ) by alkaline electrolysis powered by the Brazilian energy grid. A project of hydrogen production with a lifetime of 20 years had been evaluated by economical and sensitivity analysis. The production capacity (8.89 to 46.67 kg H2/h) production volume (25 to 100%) hydrogen sale price (1 to 5 USD/kg H2 ) and the MAR rate were varied. Results showed that at 2 USD/kg H2 all H2 production plant sizes are economically viable. On this condition a payback of fewer than 4 years an IRR greater than 31 a break-even point between 56 and 68% of the production volume and a ROI above 400% were found. The sensitivity analysis showed that the best economic condition was found at 35.56 kg H2/h of the plant size which generated a net present value of USD 10.4 million. The cost of hydrogen varied between 1.26 and 1.64 USD/kg and a LCOH of 37.76 to 48.71 USD/MWh. LCA analysis showed that the hydrogen production project mitigated from 26 to 131 thousand tons of CO2 under the conditions studied.

Our Future Energy Scenarios (FES) draw on hundreds of experts’ views to model four credible energy pathways for Britain over coming decades. Matthew Wright our head of strategy and regulation outlines what the 2021 outlook means for consumers society and the energy system itself.<br/>This year’s Future Energy Scenarios insight reveals a glimpse of a Britain that is powered with net zero carbon emissions.<br/>Our analysis shows that our country can achieve its legally-binding carbon reduction targets: in three out of four scenarios in the analysis the country reaches net zero carbon emissions by 2050 with Leading the Way – our most ambitious scenario – achieving it in 2047 and becoming net negative by 2050.

BENOPT an optimal material and energy allocation model is presented which is used to assess cost-optimal and/or greenhouse gas abatement optimal allocation of renewable energy carriers across power heat and transport sectors. A high level of detail on the processes from source to end service enables detailed life-cycle greenhouse gas and cost assessments. Pareto analyses can be performed as well as thorough sensitivity analyses. The model is designed to analyse optimal biomass and hydrogen usage as a complement to integrated assessment and power system models

Direct air capture (DAC) is considered one of the mitigation strategies in most of the future scenarios trying to limit global temperature to 1.5 ◦C. Given the high expectations placed on DAC for future decarbonisation this study presents an extensive review of DAC technologies exploring a number of techno-economic aspects including an updated collection of the current and planned DAC projects around the world. A dedicated analysis focused on the production of synthetic methane methanol and diesel from DAC and electrolytic hydrogen in the European Union (EU) is also performed where the carbon footprint is analysed for different scenarios and energy sources. The results show that the maximum grid carbon intensity to obtain negative emissions with DAC is estimated at 468 gCO2e/kWh which is compliant with most of the EU countries’ current grid mix. Using only photovoltaics (PV) and wind negative emissions of at least −0.81 tCO2e/tCO2 captured can be achieved. The maximum grid intensities allowing a reduction of the synthetic fuels carbon footprint compared with their fossil-fuels counterparts range between 96 and 151 gCO2e/kWh. However to comply with the Renewable Energy Directive II (REDII) sustainability criteria to produce renewable fuels of non-biological origin the maximum stays between 30.2 to 38.8 gCO2e/kWh. Only when using PV and wind is the EU average able to comply with the REDII threshold for all scenarios and fuels with fuel emissions ranging from 19.3 to 25.8 gCO2e/MJ. These results highlight the importance of using renewable energies for the production of synthetic fuels compliant with the EU regulations that can help reduce emissions from difficult-to-decarbonise sectors.

This report aims to summarise the status of the European hydrogen market landscape. It is based on the information available at the European Hydrogen Observatory (EHO) platform the leading source of data and information on hydrogen in Europe (EU27 EFTA and the UK) providing a full overview of the hydrogen market and the deployment of clean hydrogen technologies. As of the end of 2022 a total of 476 operational hydrogen production facilities across Europe boasting a cumulative hydrogen production capacity of approximately 11.30 Mt were identified. Notably the largest share of this capacity is contributed by key European countries including Germany the Netherlands Poland Italy and France which collectively account for 56% of the total hydrogen capacity. The hydrogen consumption in Europe has been estimated at approximately 8.23 Mt reflecting an average capacity utilisation rate of 73%. It's worth highlighting that conventional hydrogen production methods encompassing reforming by-product production from ethylene and styrene and by-product electrolysis collectively yield 11.28 Mt of hydrogen capacity. These conventional processes are distributed across 376 production facilities constituting 99.9% of the total production capacity in 2022. Throughout the year 2022 there were no newly commissioned hydrogen production facilities that integrated carbon capture technology into their operations. Additionally a notable presence of water electrolysis-based hydrogen production projects in Europe was identified. There was a total of 97 water electrolysis projects with 67 of them having a minimum capacity of 0.5 MW resulting in a cumulative production capacity of 174.28 MW. Furthermore 46 such projects were found to be under construction and are anticipated to contribute an additional 1199.07 MW of water electrolysis capacity upon becoming operational with the estimated timeframe ranging from January 2023 to 2025. A significant 87% of the total hydrogen production capacity in Europe is dedicated to onsite captive consumption indicating that it is primarily produced and used within the facility. The remaining 13% of capacity is specifically allocated for external distribution and sale characterizing what's known as merchant consumption. Despite the prevailing dominance of captive hydrogen production within Europe it's noteworthy that thousands of metric tonnes of hydrogen are already being traded and distributed across the continent. These transfers often occur through dedicated hydrogen pipelines or transportation via trucks. In 2022 an example of this growing trend was the hydrogen export from Belgium to the Netherlands which emerged as the single most significant hydrogen flow between European countries constituting a substantial 75% of all hydrogen traded in Europe. Belgium earned distinction as Europe's leading hydrogen exporter with 78% of the hydrogen that flowed between European countries originating 6 from its facilities. Conversely the Netherlands played a pivotal role as Europe's primary hydrogen importer accounting for an impressive 76% of the hydrogen imported into the continent. The rise of the clean hydrogen market in Europe coupled with the European Union's ambition to import 10 Mt of renewable hydrogen from non-EU sources by 2030 is expected to drive an increase in hydrogen flows both exports and imports among European countries. In 2022 the total demand for hydrogen in Europe was estimated to be 8.19 Mt. The biggest share of hydrogen demand comes from refineries which were responsible for 57% of total hydrogen use (4.6 Mt) followed by the ammonia industry with 24% (2.0 Mt). Together these two sectors consumed 81% of the total hydrogen consumption in Europe. Clean hydrogen demand while currently making up less than 0.1% of the overall hydrogen demand is notably driven by the mobility sector. Forecasts project an impressive growth trajectory in total hydrogen demand for Europe over the coming decades. Projections show a remarkable 127% surge from 2030 to 2040 followed by a substantial 63% increase from 2040 to 2050. Considering the current hydrogen demand there is a projected 51% increase until 2030. Throughout the three decades under examination the industrial sector is anticipated to maintain its predominant position consistently demonstrating the highest demand for hydrogen. However this conclusion refers to average values and variations that may exist. The total number of Hydrogen Fuel Cell Electric Vehicles (FCEV) registrations in Europe in 2022 was estimated at 1537 units. In comparison to the previous year the number of registrations increased by 31%. This surge in registrations has had a pronounced impact on the overall FCEV fleet's evolution in Europe which increased from 4050 units to 5570 (+38%). Notably passenger cars dominated the landscape constituting 86% of the total FCEV fleet. Exploring the latest advancements in hydrogen infrastructure across Europe in 2022 the hydrogen distribution network comprised spanning a total length of 1569 km. Within Europe the largest networks are situated in Belgium and Germany at 600 km and 400 km respectively. Of particular importance is the cross-border network of France Belgium and the Netherlands spanning a total of 964 km. To keep pace with the rising number of Fuel Cell Electric Vehicles (FCEVs) on European roads and promote their wider integration it is key to ensure sufficient accessibility to refuelling infrastructure. Consequently many countries are endorsing the establishment of hydrogen refuelling stations (HRS) so that they are publicly accessible on a nationwide scale. More recharging and refuelling stations for alternative fuels will be deployed in the coming years across Europe enabling the transport sector to significantly reduce its carbon footprint following the adoption of the alternative fuel infrastructure regulation (AFIR). Part of the regulation's main target is that hydrogen refuelling stations serving both cars and lorries must be deployed from 7 2030 onwards in all urban nodes and every 200 km along the TEN-T core network. Since 2015 the total number of operational and publicly accessible HRS in Europe has grown at an accelerated pace from 38 to 178 by the summer of 2023. Germany takes the lead having the largest share at approximately 54% of the total number of HRS with 96 stations currently operational. The majority of the HRS (89%) are equipped with 700 bar car dispensers. In 2022 the levelized production costs of hydrogen generated through Steam Methane Reforming (SMR) in Europe averaged approximately 6.23 €/kg H2. When incorporating a carbon capture system the average cost of hydrogen production via SMR in Europe increased to 6.38 €/kg H2. Additionally the production costs of hydrogen in Europe for 2022 utilizing grid electricity averaged 9.85 €/kg H2. Hydrogen production costs through electrolysis with a direct connection to a renewable energy source had an average estimated cost of 6.86 €/kg. As of May 2023 Europe's operational water electrolyser manufacturing capacity stands at 3.11 GW/year with an additional 2.64 GW planned by the end of 2023. Alkaline technologies make up 53% of the total capacity. Looking ahead to 2025 ongoing projects are expected to raise the total capacity to 7.65 GW/year. Fuel cell deployment in Europe has showed an increasing trend over the past decade. The total number of shipped fuel cells were forecasted on around 11200 units in 2021 and a total capacity of 190 MW. The most significant increase in capacity occurred between 2018 and the forecast of 2021 (+148.8 MW).

Liquid hydrogen (LH2) aircraft have the potential to achieve carbon neutrality. However if the hydrogen is produced using electricity grids that utilise fossil fuel they have a non-zero carbon dioxide (CO2) emission associated with their well-to-wing pathway. To assess the potential of LH2 in aviation decarbonisation an energy systems comparison of large commercial LH2 liquified natural gas (LNG) conventional Jet-A and LH2 dual-fuel aircraft is presented. The performance of each aircraft is compared towards 2050 over which three system changes occur: (1) LH2 aircraft technology develops; (2) both world average and region-specific grid electricity which is used to produce the hydrogen decarbonises; and (3) the International Air Transportation Association (IATA) emissions targets which are used to restrict the passenger-range performance of each aircraft tighten. In 2050 the emissions of all aircraft are thus constrained to 0.063 kg-CO2/p-km relative to 0.110 kg-CO2/p-km for the unconstrained Jet A fuelled Boeing 787-8. It is estimated that in this year an LH2 aircraft powered by fuel cells and sourcing world average electricity can travel 6000 km 20% further than the conventional Jet A aircraft that is also constrained to meet the IATA targets but not as far as the LNG aircraft. At its maximum range the LH2 aircraft carries 84% of the Jet A passenger demand. Analysis using region-specific hydrogen indicates that LH2 aircraft can travel further than LNG aircraft in North America only accounting for 17% of the global demand. 1.59 times the current aviation energy consumption is required if all conventional aircraft are replaced with LH2 designs. Under stricter emissions constraints than those outlined by the IATA LH2 outperforms LNG in Europe and the Americas accounting for 41% of the global demand. Also in these regions the range energy consumption and passenger capacity of LH2 aircraft can be improved upon by combining the advantages of LH2 with LNG in dual-fuel aircraft concepts. The use of LH2 is therefore advantageous within several prominent niches of a future decarbonising aviation system.

Aviation contributes to anthropogenic climate change by emitting both carbon dioxide (CO2) and non-CO2 emissions through the combustion of fossil fuels. One approach to reduce the climate impact of aviation is the use of hydrogen as an alternative fuel. Two distinct technological options are presently under consideration for the implementation of hydrogen in aviation: hydrogen fuel cell architectures and the direct combustion of hydrogen. In this study a hydrogen demand model is developed that considers anticipated advancements in liquid hydrogen aircraft technologies forecasted aviation demand and aircraft startup and retirement cycles. The analysis indicates that global demand for liquid hydrogen in aviation could potentially reach 17 million tons by 2050 leading to a 9% reduction in CO2 emissions from global aviation. Thus the total potential of hydrogen in aviation extends beyond this considering that the total market share of hydrogen aircraft on suitable routes in the model is projected to be only 27% in 2050 due to aircraft retirement cycles. Additionally it is shown that achieving the potential demand for hydrogen in aviation depends on specific market prices. With anticipated declines in current production costs hydrogen fuel costs would need to reach about 70 EUR/MWh by 2050 to fulfill full demand in aviation assuming biofuels provide the cheapest option for decarbonization alongside hydrogen. If e-fuels are the sole option for decarbonization alongside hydrogen which is the more probable scenario the entire hydrogen demand potential in aviation would be satisfied according to this study’s estimates at significantly higher hydrogen prices approximately 180 EUR/MWh.

To study the effect of hydrogen-blended natural gas on the combustion stability and emission of domestic gas water heater a test system is built in this paper taking a unit of the partial premixed burner commonly used in water heaters as the object. Under the heat load of 0.7~2.3kW the changes of flame shape burner temperature and pollutant emission of natural gas with hydrogen volume ratio of 0~40% are studied with independent control of primary air supply and mixing. The results show that: with the increase of hydrogen blending ratio the inner flame height increases firstly and then reduces while the change of burner temperature is opposite. The maximum inner flame height and the minimum temperature of the burner both appear at the hydrogen blending ratio of 10~20%. It can be seen that the limit of hydrogen blending ratio which can maintain the burner operate safely and stably under rated heat load is 40% through the maximum temperature distribution on the burner surface. The CO emission in the flue gas gradually decreases with the increase of hydrogen blending ratio while the NOx emission fluctuates slightly when the hydrogen blending ratio is less than 20% but then decreases gradually.