NOTE:  

A home page with brief technical information, some conceptual detail, a few images and links is at the address: http://home.iprimus.com.au/fredb19/solarhouse/house01.htm

CURRENT INSTALLATION AND PERFORMANCE INFORMATION

This page provides the latest installation information and data gathered on various performance parameters.

The contribution of wind through the wind turbine system is a negligible component and has not been referenced.

At this stage we are operating under a grid-connect system with both import and export capability and we are not using the batteries other than in a UPS (uninterruptible power supply) mode.  The batteries are being maintained in a fully charged status by the Plasmatronics Solar Controller.  Under this mode of operation we are importing power from the grid during all periods when the solar renewables component is less than the household load.   We are exporting as soon as solar renewables exceeds household load.  The batteries are only (automatically) used if local authority mains power is totally lost.

The reason for this mode of operation (ie, effectively not using battery power on a daily basis) is due to our continuing development of the control systems and negotiation with the Inverter manufacturers toward provision of suitable software which we wish to use to control import on-peak and off-peak factors to our advantage.  We expect over time that we can improve cost effectiveness of the system. 

In addition, not using the batteries on a daily basis has an advantage in dramatically increasing their expected life due to the reduced, and negligible, depth of discharge levels.

We did run the system on total disconnection from mains power for approximately one month (in January 2003) to test and collect data.  The system worked fine. We then switched across to total grid connect/export mode (with batteries in standby mode) and continued data collection.

The sale of excess energy over imported energy since the system was installed (approximately 20 month period) shows a delightful positive result:

The local supply authority (Energex) agreement enables export of (unlimited) excess energy which they will pay us at the rate of $0.08/kWH.

The approximate prices we pay for imported energy is $0.12/kWH on-peak, and $0.05/kwh off-peak.

Included in our connection agreement was the refund of $630 for Energex ownership of our REC credits  (renewable energy credits) for the next 5 years, based on their estimate of an approximate 5 year, 34MWH production capacity

A few selected graphs are provided below.  We are still experimenting with data collection and learning methods of  presentation.  This information will be occasionally updated to reflect our experience and the accumulation of data.

Solar Panel Power Generation

Calculated from (Solar Panel amps * connected Battery Voltage) at 15 minute intervals over an approximate 18 month period.

 Note that the average instantaneous power generated is varying between approximately 2500 watts to 2800 watts.

The slight drop in the y axis curve (near the middle of the x-axis ) is the winter period 2003.

The occasional large, short duration, drops in the y-axis data is due to overcast days during inclement weather (very much reduced solar energy).  The occasional short duration negative excursions are due to days when imported power (from the local authority) exceeded solar generated power.

 The theoretical maximum power output for the solar panel system is approximately 3050 watts.  Hence we can deduce the overall system solar power generation efficiency of approximately:

= Average power generated/theoretical power output of panels

= (2600/3050)*100 % 

= 85%

The graph above shows the average daily household load energy consumption at 15 minute intervals over an approximate 18 month period.

The average daily consumption is about 8 kWH per day.  This is averaging about 2 kWH per day less than the original project calculated average load (see web page on solar calculations - http://home.iprimus.com.au/fredb19/solarhouse/solarcalc.htm )

Note the occasional large peak loads, the highest peaking at over 18 kWatts (days when the tumble dryer, arc welder and other high energy devices have been operated).

This web page is maintained by Fred & Jeanette Birkbeck