Micro Urban Power Generation System

Introduction

This site contains information on my micro power generation (backyard project). By "micro" I mean small amounts of power, currently not enough to supply the house. The output is used to power landscape lighting, a stream , and other small items. The system is a hobby that seems to keep growing, starting out as a cheap set of solar panels that claimed to generate 45 Watts at 12V. It is now a system comprising 700 Watts of solar panels, a wind turbine, homemade data loggers and controllers. Power generated is stored in a bank of 6 golf cart batteries rated at 690 amp-hours total

Why Urban? Beacuse this site is located in a very populated area on the eastern coast of the U.S.

The following links show live data from the system:

Wind / Solar Data Tables (updated once a minute) These tables show the battery voltage, incomming current, outgoing current , amp hours and watt hours.

Wind / Solar Graph (updated once a minute) A graph of today's power generation

Measurement Information for the above links

Actual current and voltage measurements are performed by a Basic Stamp (BS2PX) from Parallax. Approximately every 2 seconds each of 5 measuring devices is checked and after 1 minute the totals for each reading are averaged.

The averaged readings for each device, along with the maximum and minimum values, and the date and time are transmitted wirelessly to a PC running a .Net application (APP) located in the house. The APP reads the data, and the stores it in a MS Access database table. It then retrieves specific data from the table, creates as Javascript file which is then uploaded to this web site, along with the graph.

Deeper Technical

The core of the measurement system is a MAX186, 8 channel, 12 bit analog to digitial converter (ADC), currently 5 of the channels are being used. One channel is used to measure battery voltage using a voltage divider, while the other 4 are each connected to ZAP25 25 amp Hall effect current sensors from Amploc.

The MAX186 is attached to the Basic Stamp BS2PX .The software programmed on the stamp performs the following looping routine

1. Gets digital data from one channel of the MAX186, repeats this 10 times and the generates a value from this average. The value is then added to a increasing variable. At the same time it checks if the value is the maximum or minimum for the last minute. If so it then stores off that value as well.
2. This is repeated for the 4 remaining channels, then there is a 2 second pause before the next reading loop
3. This loop is repeated 30 times for a duration of approximately 1 minute
4. For each channel the increasing values are then averaged , and along with the maximum and minimum values sent to a 912 MHz tranceiver (Parallax) , which transmits the data.
5. Variables are reset and steps 1-5 repeat

A VB.Net program that I wrote and have running as a service on my PC , listens for communication from its own connected 912 MHz transceiver. Once it receives data, it stores it off to an MS Access table. It then queries the table, generates the chart/graph, and collects the data for the HTML table. The information is then uploaded to this site.