Fersiynau electronig


  • 2019-Power variability of tidal-stream energy

    Llawysgrif awdur wedi’i dderbyn, 6 MB, dogfen-PDF

    Embargo yn dod i ben: 1/07/20

    Trwydded: CC BY-NC-ND Dangos trwydded

Dangosydd eitem ddigidol (DOI)

Temporal variability in renewable energy presents a major challenge for electrical grid systems. Tides are considered predictable due to their regular periodicity; however, the persistence and quality of tidal-stream generated electricity is unknown. This paper is the first study that attempts to address this knowledge gap through direct measurements of rotor-shaft power and shore-side voltage from a 1 MW, rated at grid-connection, tidal turbine (Orkney Islands, UK). Tidal asymmetry in turbulence parameters, flow speed and power variability were observed. Variability in the power at 0.5 Hz, associated with the 10-min running mean, was low (standard deviation 10–12% of rated power), with lower variability associated with higher flow speed and reduced turbulence intensity. Variability of shore-side measured voltage was well within acceptable levels (∼0.3% at 0.5 Hz). Variability in turbine power had <1% difference in energy yield calculation, even with a skewed power variability distribution. Finally, using a “t-location” distribution of observed fine-scale power variability, in combination with an idealised power curve, a synthetic power variability model reliably downscaled 30 min tidal velocity simulations to power at 0.5 Hz (R2 = 85% and ∼14% error). Therefore, the predictability and quality of tidal-stream energy may be undervalued in a future, high-penetration renewable energy, electricity grid.
Iaith wreiddiolSaesneg
Tudalennau (o-i)1061-1074
Dyddiad ar-lein cynnar1 Gorff 2019
Dynodwyr Gwrthrych Digidol (DOIs)
StatwsCyhoeddwyd - 15 Medi 2019
Gweld graff cysylltiadau