AOC 15 user manual Kilowatt-Hour Meter Applications, Anemometers, Output Analysis Worksheet

10.0 System Monitoring 86

The following sections discuss the various monitoring systems of the AOC 15/50.

10.1Kilowatt-Hour Meter Applications

Some utilities may require the use of detented, unidirectional kilowatt-hour (kWh) meters: one to read the energy supplied by the utility and another to read the energy absorbed by it. This enables the utility to pay the avoided cost rate for the energy it buys and to charge the standard rate for the energy it consumes. A detented kWh meter can be used to monitor power production. The most useful information for evaluating system performance is obtained by comparing the kilowatt-hours generated with the average wind speed over the same period. The relevant parameters can be measured using a dedicated kWh meter (energy production) and an anemometer (wind speed).

Net billing refers to the installations where a single kWh meter is allowed to run forwards or backwards depending upon whether the system is consuming or producing energy. The kWh meter indicates the net energy flow and energy is valued at the same rate for consumption and production.

10.2Anemometers

The AOC 15/50 has two anemometers which are boom-mounted across two tower legs, approximately 10 m (32 feet) below the tower top casting. The PLC samples the wind speed measured by each anemometer every second and calculates 8 second and 128 second averages from the sampled data.

10.3Output Analysis

One of the best methods for evaluating a wind system's performance is to monitor energy production. Unless there is an obvious mechanical or electrical fault, wind speed and kilowatt- hour production should be recorded for at least one month after the wind turbine has started running and ideally afterwards also, either continuously or at regular intervals, so that any drastic changes in performance can be noted and investigated. Note that a number of factors can affect output, including wind velocity, wind turbine maintenance, temperature, humidity, etc. Recording these parameters will help evaluate system performance, as well as understand system operation.

10.4Output Analysis Worksheet

The system monitoring checklist (see Appendix G) will assist in evaluating system performance, by providing the information necessary to reach an informed conclusion. It can be used for routine system monitoring, as well as to observe and understand normal system function. Energy

NOTICE: Use of the material contained in this document is subject to the warning on page Iv and the disclaimer on page v of this document.

DOC012R02 AOC 15/50 User Manual Nov 2001