shows available roof space for array expansion
The solar array atop the office complex at Holy Cross Anglican School (24 280W panels; 5MWatt overall) had been up and running continuously through about March 4, 2012. At this time, a problem developed -- potentially related to a storm that blew through -- causing a loss of power. Our contractor, Baker Renewable Energy, proposed several possible causes, and a bad fuse was found to be the culprit. On April 1, I arrived on site with a replacement, which was installed and tested. This fixed the problem. I also carried with me a number of spares should the problem arise again. The system has been back online without interruption since that time.
Surveys of power bills from Belize Energy and Light, plus discussions with local staff, revealed that on average the array seems to be making a 20- 30% difference (reduction) in monthly billing costs against the meter that measures usage from the Computer Learning lab and composting toilet facility. Unfortunately, there also appears to be some -- perhaps significant -- solar-power generated that goes unused and gets fed back onto the grid.This may occur when the computer lab is not being used (computers are shut down, A/C is set a bit higher) and/or when the composting toilet facility is at minimal load. A second meter, which is on a different circuit (office itself, on-site maintenance man's apartment, school kitchen, dining room facility, many classrooms) is not tied into the solar panel, and so its bill is not affected. Power loss could be mitigated if the solar array were also connected to this second metered circuit.
We also surveyed the office complex roof where the current array is located, and determined that there is room for another 12 panels on this particular stretch of roof.
Thus, we believe we are ready for a Phase 2 project which will (1) increase the capacity of the present system; and (2) tie the system into both meters in such a way that it minimizes power loss; (3) continue to encourage Belize Electricity Limited to buy back power that we are generating and not using (currently they have no program in place to do that).
I've posted some pictures of the recent survey of roof space available to expand our current array with the hope of having a solid plan for a Phase 2 project in place sometime over the summer. Thanks again to all for supporting this wonderful project!!
Measuring for available expansion space
present array micro-inverter hub
close up of micro-inverter hub