The set up

The set up
5.46mm jet delivering 0.68 l/s to the pelton which is rotating at 900 rpm and generating 135 watts into the grid.

Saturday, 19 December 2015

The system at full stretch

Minimal script in this post to counterbalance the wordiness of the last two,-  just pictures taken this morning of the system working at full capacity:
Gathering the flow

Removing the trash

2.84 lps bottom jet, 0.3 top jet; 1200 rpm

Spent water returning to the stream

3 amps;  305 v dc

Relative humidity 33%, temp 26.8 ℃ (ambient 95%, 14℃)

Working in turbine mode

302 v ± 3  - very steady cf MPPT mode

Wattson: my in-house visibility of output

Sunny Beam: my in-house visibility of cumulative energy

Wattson Anywhere: my on-line visibility of power and energy output, captured the following day


The really accurate figure for energy output for this one day was 18.78 kWh, giving a mean power output of 782.6 watts.  The Wattson and SMA data seen above are not so accurate. The whole system efficiency for the day can therefore be calculated to be 47~ 48% (782.6 / [53.6 x 3.14 x 9.81] ), the inverter efficiency to be 85 ~ 86%, and the pelton/alternator conversion efficiency to be 55 ~ 56% ( [3 x 302] / [53.0 x 3.14 x 9.81] ).

With the whole system efficiency coming in at 47~48%, there doesn't look to be a significant improvement over last year (see here) when I was running in MPPT mode and two equal sized jets.  So maybe turbine mode and having most water coming through one big bottom jet doesn't confer any advantage.

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