1. Other similar projects (HyDeploy, H21, Hy4Heat, Hydrogen Homes, GRYHD)
The Natural Energy of Hydrogen is a pioneer in Portugal; however, this does not mean that we are the only ones in the world. In some of the more developed countries, especially in Europe, there are already projects (developed and under development) aimed at using green hydrogen as a source of energy.
Below are some of the most relevant projects that confirm the importance of investing in green hydrogen.
2. Suitability of networks, in particular polyethylene, for the distribution of H2 and NG/H2 mixtures
Various studies show that the existing infrastructure, designed for the distribution of natural gas, is sufficient and safe for the distribution of H2.
The existing network, which will carry H2/GN mixtures with hydrogen percentages of up to 20%, will not differ from NG networks. The line to be built for the transmission of H2 up to the PRM50 will therefore be licensed according to the applicable standard for NG.
In order to confirm the good performance of polyethylene (PE) for transporting H2, we shall monitor the permeation phenomena by measuring the H2, oconcentration, the explosivity in manholes along the line, and also check the effectiveness of insulation valves. At the same time, the programme to investigate leakage along the H2, line, with specific detectors, will be strengthened in order to control more effectively the occurrence of leakage due to construction defects and, above all, to the increased permeability of the PE to H2.
Furthermore, the burning of H2 produces an invisible flame and requires the use of extinguishers different from those normally used by distributors. The project also requires the training of technicians involved in the operation of the network. It specifically addresses the differences in the process of burning and extinguishing possible fires, in addition to the operation of the injection equipment to be installed.
Materials engineering services include approval/certification of the design, materials and procedures, as well as inspection and monitoring of hydrogen line construction and mixing unit construction, and analysis (sampling and sample processing) of the mixture to be distributed and testing of materials exposed to hydrogen.
3. H2-ready Boilers/Heaters
The development and commercial scale of equipment capable of receiving and operating 100% on hydrogen is expected in the future.
4. Impact of blending on gas meters.
With the type of meters we use H2/GN measurement may be inaccurate for larger % of H2. This matter is being studied internationally. As the volume of mixture will grow as the % of H2 increases, existing meters may be unable to measure the gas to high %, or to H2 a 100%. If the gas is properly measured (by volume), the impact on the metering of the energy consumed and the monthly consumer expenditure should be zero.
5. Limits of blending using current equipment setup
Current appliances are approved with a gas limit that has 23% H2, but this does not mean that they are approved to burn mixtures with that % H2. This type of approval provides for appliances to be certified for mixtures up to about 10% (to be confirmed).