Evolution of a microhydro system.

Microhydro has been used on this site for many decades. Remnants of an wooden flume date back to the 1950's. EA has been working for this customer for over a decade. This site has 120' of vertical drop and a highly variable microhydro resource, completely reliant on winter rains in southwestern British Columbia.

When EA started at this site, there was a single-nozzle Stream Engine, made by Energy Systems and Design. It was running a single nozzle and delivering up to 30 A @ 24 VDC (800 watts) during periods of high rain, but would slow dramatically once the rains stopped.

In 2005, asecond turbine was added by fabricating a custom PVC valve solution for the very small space in the current turbine shed. This significantly boosted the power output during high rain times, and allowed for different combinations of turbines to be manually controlled according to rainfall.

Summer of 2007, the intake was upgraded to a modern, low-maintenance coanda screen unit with integrated clean-out valves. The main power system was upgraded to a modern 48V system and the existing microhydro turbines were adjusted easily for the increase in voltage.

Summer 2009 was time for a complete rebuild. The existing power shed was removed and a new foundation poured and shed built to our specifications. A custom aluminum base and tailrace was constructed, which fit into the custom foundation. A custom steel intake manifold was designed and fabricated for ultra-low pipe friction.

EA developed an automated control system which monitors the real-time performance of this system and automatically adapts to achieve peak output. This control system is internet enabled and has both remote and on-site manual bypasses, allowing the system to be manually operated if desired.

It operates by monitoring the dynamic pressure in the intake, the electrical output of the turbines, and the battery voltage of the system. The system will automatically open or close valves to achieve the highest possible output given varying water volume and electrical needs.

We are still working with the control system during different volumes of rainfall for optimal performance. Early estimates suggest the daily kWh from this system to be around 2x due to the additional turbine and the automation.