Nowadays, mainly diesel generators are used as an off-grid solution for backup power, but this causes CO2 and GHG emissions (especially NOx and particulates), noise emissions and the effects of the volatile diesel market influences operating costs. Renewable energy, such as...
Nowadays, mainly diesel generators are used as an off-grid solution for backup power, but this causes CO2 and GHG emissions (especially NOx and particulates), noise emissions and the effects of the volatile diesel market influences operating costs. Renewable energy, such as solar or wind, is becoming increasingly competitive with traditional solutions for off grid applications. Unlike grid-connected systems, their economic justification is not influenced by prevailing electricity tariffs or fuel supply costs, but supply intermittency and availability have to be matched with suitable storage systems to provide a good alternative to the classic diesel generators.
Green hydrogen production by means of water electrolysis has been proposed as a feasible solution to fill the gaps between demand and production. Off-grid electrolysis and hydrogen storage have the key advantage of being able to manage both the long term and short term transient variations in renewable supply, whereas batteries cannot manage the seasonal variations unless very large battery stores are specified.
The main underlining purpose of the ELY4OFF project is the development and demonstration of an autonomous off-grid electrolysis system linked to renewable energy sources. The PEMWE (Polymer Electrolyte Membrane Water Electrolyser) industrial prototype will be sized to respond to 50 kW, and will be directly linked to track the solar photovoltaic power source producing over 1.5 tonnes of hydrogen per year for different end uses ensuring cold start and rapid response to changes. The specific objectives related to the electrolyser will be high system efficiency and low cost, very high efficiency cell, robustness and safety (20 bar), flexibility for direct coupling to RES, durability, and communication and control capabilities. The demonstration period in a relevant environment (TRL 6) will last 8 months and will take place in Huesca, Spain.
Other additional objectives of the project are optimized design, CAPEX competitiveness, the study of relevant regulations, codes and standards, detailed cost analysis, new business models, assessment of potential target markets, analysis of specific business models, and dissemination and exploitation of project results.
The outcomes achieved during the reporting period nº2 (October 2017 to March 2019) can be summarized as follows:
- Demonstration period started on 11 March 2019. 24 kg of green hydrogen produced until end of March 2019.
- Study covering specific national requirements and how to overcome barriers in four different countries (Denmark, Scotland, Sweden, France) has been elaborated.
- A detailed Life Cycle Assessment (LCA) has been developed in order to estimate the potential environmental impacts associated to the project compared to two alternative scenarios (wind energy and electricity from the grid)
- Steady-state and dynamic testing of the down-selected MEA and stack components at large-scale has been completed. Based on these results the MEA was considered suitable for use in the PEMWE stack of the demonstration system
- The required 13 units of novel DC/DC converters has been built, assembled and delivered on time. They fulfil the required operation specifications: the maximum temperature limit, the minimum efficiency, and the required MPPT strategy.
- The final configuration of the Hybrid Storage System is composed by: 36 kWh lead acid batteries (between 20 to 36 hours of autonomy depending on the season), 4.5 kW stationary low temperature PEM fuel cell to cover safety loads when the lead acid batteries are discharged, and a H2 capacity of 7 kg at low pressure tank (20 bar), and 23 kg at high pressure tank (350 bar).
- Several energy storage and management architectures are being assessed.
- The overarching control and communication system (C&CS) which governs the microgrid allows a safe, reliable, robust and energy efficient operation of the PEMWE, PE and peripherals.
- User-friendly SCADA interface design which allows access to every subsystem to see status.
- An assessment of potential target markets has been accomplished
- Three main Business Cases were modelled and simulated: Isolated site electrification in Tenerife (Spain) and Edinburgh (Scotland), gas grid injection in Millau (France) and Shetland Islands (Scotland) and mobility application in Miallau (France) and Hofn (Iceland).
- 4 open access publications have been launched, one of them peer-reviewed.
- 10 participations in conferences and workshops.
ELY4OFF’s ambition is to provide breakthroughs in Polymer Electrolyte Membrane water electrolyser (PEMWE) technology coupled to an off-grid energy source. The project expects to achieve a series of significant techno-economical advances pushing PEMWE technology well beyond its today’s capabilities looking for off-grid deployment into existing and new immerging markets. The most significant improvements expected from ELY4OFF are related off-grid operation, which is directly associated with the following topics: increase of stack and system efficiency, Capex in novel system aligned with programme objectives, dynamic capabilities, reduction of tolerable minimum part load, acceleration of ramp-up from minimum to full load, acceleration of ramp-down from full load to min, acceleration of cold start from min to max power, and direct connection with the PV source. These topics have been considered within the specifications set up for all the elements of the system, and they will be checked during the demonstration period scheduled for the last 8 months of the project.
The potential impacts of the project can be classified into the following groups:
- Objectives and targets are expected to achieve and in some cases surpass the targets for 2017 in terms of efficiency and costs for PEMWE. As regards to efficiency, lifetime and dynamic operation, the targets of the project are totally aligned with the expected contribution of these systems to reach the targets in horizon 2017 and 2020. ELY4OFF targets are expected to be more exigent than the key performance indicators expressed in the topic in order to pave the way for future developments aimed to reach the targets in the horizon 2020.
- 6 target markets will be covered through the assessment of specific business cases applied to real installations. One of them has already been done, covering the electrification of isolated sites.
- The system proposed within ELY4OFF has a direct impact on reduction of CO2 emissions in Hydrogen production
More info: http://www.ely4off.eu.