Experimental investigation of a novel power storage system based on the osmosis process
Moss, Harry (2026)
Diplomityö
2026
School of Energy Systems, Energiatekniikka
Kaikki oikeudet pidätetään.
Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi-fe2026051546021
https://urn.fi/URN:NBN:fi-fe2026051546021
Tiivistelmä
In this Master’s thesis a prototype energy storage test rig was sent to the LUT University from Germany by the company Hybrid Osmosis Pump Energy Storage which will be referred to as HOPES continuing on. The prototype energy storage test rig was to be rebuilt for further research to be conducted on it.
The original plan was to conduct experiments to find out how the salinity of the water circulating in the saltwater circuit would affect the process. The membranes used in the experiments were of the reverse osmosis type, even though they were used in a pressure retarded osmosis process. The reason for this is that reverse osmosis membranes were readily available in the 4040-standard size, but forward osmosis membranes or pressure retarded osmosis membranes were not. Another reason was that the previous research done with the same test rig in Germany was done successfully with reverse osmosis membranes.
The experiments concerning the effects of the salinity could not be carried out because the membranes used in the process failed during the first test runs. After the failure of the first membrane another membrane from a different manufacturer was used to see if it would fail as well. The second membrane did fail, and it failed in the same way as the first membrane. The membrane manufacturer’s technical team informed that any flow of water to the opposite direction than is intended would cause delamination of the membrane. This seems to be what happened to the membranes in our experiments.
The Germans had success with their research using reverse osmosis membranes with the same test rig, but the results could not be replicated here in LUT University. Any further research on this process should be done with pressure retarded osmosis membranes.
The original plan was to conduct experiments to find out how the salinity of the water circulating in the saltwater circuit would affect the process. The membranes used in the experiments were of the reverse osmosis type, even though they were used in a pressure retarded osmosis process. The reason for this is that reverse osmosis membranes were readily available in the 4040-standard size, but forward osmosis membranes or pressure retarded osmosis membranes were not. Another reason was that the previous research done with the same test rig in Germany was done successfully with reverse osmosis membranes.
The experiments concerning the effects of the salinity could not be carried out because the membranes used in the process failed during the first test runs. After the failure of the first membrane another membrane from a different manufacturer was used to see if it would fail as well. The second membrane did fail, and it failed in the same way as the first membrane. The membrane manufacturer’s technical team informed that any flow of water to the opposite direction than is intended would cause delamination of the membrane. This seems to be what happened to the membranes in our experiments.
The Germans had success with their research using reverse osmosis membranes with the same test rig, but the results could not be replicated here in LUT University. Any further research on this process should be done with pressure retarded osmosis membranes.