MAILBOX: Hydro Article Concerns

The Janowski turbine (from this current issue).

I have for many years tried to lift the quality of domestic-scale hydro turbine installations to ensure that they are safe and compliant with national standards and codes and generally follow best global practices. I am somewhat appalled by seven serious issues in the “Working, Playing and Living with Renewable Energy” article published in Home Power’s May/June 2015 issue.

  • The turbine’s magnetic rotor is not covered and is a rotational hazard.
  • Lacquer copper wire is not classed as insulation for touch safety. Exposed copper stator wire is clearly visible and could be touched when operating.
  • The resistive diversion element is bolted to a plywood wall without any heat shield. This is a fire hazard and not allowed under U.S. standards/codes.
  • According to the wiring diagram, the metal turbine body has no earth connection and, under a fault condition, could become a shock hazard. As the turbine is mounted on a plywood cover, it appears to have no earth connection.
  • The photo on page 63 shows a red positive wire to the TriStar TS45 and a green (assumed to be the negative, as there is no other wire) to the TS45. Green wire cannot be used for negative connections.
  • The TS45 is not wired per the manufacturer’s advice. If the fused disconnect was opened while the turbine was running (or the fuse was to blow), the TS45 would be damaged by overvoltage.
  • To comply with the intent of the National Electrical Code, hydroelectric systems using a diversion controller should be equipped with a second independent means of charge control to prevent overcharging the battery in the event of a component failure.

We all make the odd error; I am sure my home system has a few. However, to publish an article in Home Power that does not red-flag these installation issues is rather reckless. I hope you take action so that your readers do not assume such insulation practices are safe and code-compliant.

Michael Lawley • via email

Home Power takes safety very seriously. We admittedly dropped the ball in this instance. Our editorial crew enjoyed the homesteading history of the story and the authors’ commitment to renewable energy. The system in question is owner-installed and has evolved over the years. While it performs reliably and efficiently, we overlooked important safety and code-compliance issues during the article’s development. We’ll redouble our efforts to catch issues like this prior to publication.

Joe SchwartzHome Power Executive Editor

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