Run of River Hydroelectric Power Stations

Application Background

Run-of-the-river hydroelectric generation is a method of generating electricity from flowing rivers without making water storage or large dams. Such plants are small and only divert a small amount of the river flow from the river for power generation, and then return that water flow back to the river a small distance downstream.
These smaller plants have less impact on the river, as they don’t need to have a large dam to store water. However there is a strong regulatory requirement to ensure the river parameters are not changed during the diversion. The water parameters need to be measured very carefully at the in-flow to the power station and at the out-flow of the power station before water is returned to the river.

Application Detail

Water parameter measurement stations need to be installed at the intake and the outlet of the power station, and along the river at various points upstream and downstream from the power station. The measurements needed include water level, water flow, water quality / conductivity, and water temperature. With reliable data at these points, the operator can ensure they remain within the regulatory requirements of the state or provincial authority responsible for river management. As with all river parameter measurement, a measurement method needs to be determined. Smaller and easier probes to install such as hydrostatic pressure probes are generally preferred as the terrain conditions are often challenging. Using a large stilling well is often not practical, and also may not be allowed as these structures impact the environment. Stilling wells may be affected by seasonal flood conditions.

Typically several instruments would be connected via one SDI-12 interface, as the application requires a very low power environment and the slower speed of SDI-12 is acceptable for the application. Example instruments would be the 6542D Hydrostatic Depth Probe, the 6526 Ultrasonic Doppler Flow Meter and temperature probes. The 6537 Starflow QSD SDI-12 Ultrasonic Doppler Instrument could be used to measure water depth, water velocity and conductivity / water quality. As these installations are often in rugged mountain environments, cell phone coverage is usually not available and satellite based telemetry systems are needed. The Satellite Neon Remote Logger, either low earth orbit or equatorial earth orbit systems could be chosen.

The terrain also needs to be considered. As these installations are usually in deep valleys, the view towards the sky is less, and the high hills may block the view to the equatorial earth orbit satellite provider of your choice. If you choose a low earth orbit system (these systems transit the sky every hour or so) coverage would be available for the short period of time the low earth orbit satellite is visible from that location. A review of the local conditions, especially the view of the sky is needed to determine the best choice. There are web based tools which provide the azimuth and elevation angles to different equatorial satellite providers based on the latitude and longitude of a particular location. With the azimuth and elevation angles, the site can be reviewed to determine if use of an equatorial elevation satellite provider is practical.

As these systems are remote, primary power is generally not available and solar panel and gel cell battery would be needed. Unidata engineers calculate a power budget, to determine size of the battery and solar panel needed for particular system. When calculating power budget, geographical location and number of associated sunny days during the winter time are taken into account. This is to make sure the system is operational even with an extended period of cloudy days. Also, it is common practice to only power up the instruments when needed, for example the instruments would be powered up, perhaps one minute before the reading time, and then turned off after the reading, to conserve power. The data collected at these measurement stations would be available to view on the Neon Server using a standard web browser, and anywhere on the web provided appropriate login credentials were set up on the Neon Server for this purpose.

Finally, we would expect for collected data to be passed on using Neon Server automatic reports, to a river monitoring / hydrographic analysis software package such as Aquarius or Hydstra for more detailed river hydrographic modelling and river gauging processes.

Typical Configuration

Options for Application Specific Instruments / InputsUnidata Part NumberDescription
Ultrasonic Doppler SDI-12 Instrument - velocity, depth and temperature6527Starflow QSD Ultrasonic Doppler SDI-12/MODBUS Instrument
Ultrasonic Doppler SDI-12 Instrument - velocity, depth, temperature and EC6537Starflow QSD Ultrasonic Doppler and EC SDI-12/MODBUS Instrument
4-20mA Pressure Transmitter 6548A-B/CSubmersible Pressure Transmitter 4-20mA 5m or 10m
Double Junction Teflon-pH Probe6528CpH Probe
Dissolved Oxygen Probe7422AO2 Probe

Options for Neon Telemetry - NRL / NRT / RTU / Field UnitsUnidata Part NumberDescription
Industrial (Metal Enc) Neon Remote Logger 16 Channels3016Options Available: 3G/4G Cellular, Ethernet, Inmarsat, Iridium SBD and LoRa
Industrial (Metal Enc) Neon Remote Logger 8 Channels3008Options Available: 3G/4G Cellular, Ethernet, Inmarsat, Iridium SBD and LoRa
Industrial (Metal Enc) Neon Remote Logger 4 Channels3004/3006Options Available: 3G/4G Cellular, Iridium SBD and LoRa
Neon Remote Logger (Polycarbonate Enc) 4 Channels M Series3004M/3006MOptions Available: 3G/4G Cellular, Microsatellite, Iridium SBD and LoRa
Equatorial Orbit Satellite - Inmarsat2018F-AB0-1 or 3NRT Ethernet with single or triple Ethernet Ports with three Li Batteries
NRT Field Termination Strip2103F2018F and 2022 NRT FTS
NRT Firmware Option2303A-8M8M Extended Memory Option
NRT Firmware Option2303A-8M-CAM8M Extended Memory & Serial Camera Option
NRT Firmware Option2303A-CAMSerial Camera Option

Options for Neon Application Software - Customer ServerUnidata Part NumberDescription
Neon Application Software2302ANeon Server Software Licence Incl 5 NAL
Neon Application Software2302A-10Additional 10 NRT Access Licences
Neon Application Software2302A-20Additional 20 NRT Access Licences
Neon Application Software2302A-50Additional 50 NRT Access Licences

Options for Neon Application Software - Unidata ServerUnidata Part NumberDescription
Neon Application Software2301ANeon Data Initial Subscription Setup Fee
Neon Hosting Service2301A-01Neon Data Service Fee for 1-50 NRTs
Neon Hosting Service2301A-02Neon Data Service Fee for 51-100 NRTs
Neon Hosting Service2301A-10Neon Data Service Fee Metering

Options for Conventional Dataloggers / Field UnitsUnidata Part NumberDescription
Neon Remote Logger 16 Analog Channels / Touch Screen Display3016-00016 Ch NRL (Superseded Prologger 7001D)
Neon Remote Logger 8 Analog Channels / Touch Screen Display3008-0008 Ch NRL (Superseded Stalogger 6004D)
Neon Remote Logger 4 Analog Channels / Touch Screen Display3004M-0004 Ch NRL (Superseded Micrologger 8010C)
Starlog V4 Management Software6308A-AUEStarlog V4 Full Licence Key