By Vvon Engineering Team | Published | Updated
Separate electrical demand from kiln fuel, assess process dust and roof conditions, and model seasonal production before sizing PV.
Solar EPC & street lighting RFQ checklist (TXT)
Separate electrical consumption from kiln fuel before estimating the effect of PV. A rooftop array can offset electricity used by motors and auxiliaries; it does not directly replace gas or coal burned for process heat. An electrically heated kiln or a proposed electrification project needs a different load and engineering assessment.
What is left, once that is out of the way, is a genuine and often underestimated electrical load, and in a ceramics plant it happens to have almost exactly the shape solar wants.
The heat is gas. The motion is electric, and there is a great deal of motion.
A ceramics plant can have a useful continuous electrical load beneath the kiln process. Measure it before deciding how much PV could be consumed on site, allowing for shutdowns and maintenance. Keep the expected electricity saving separate from the kiln-fuel bill.
A brick plant's electrical load is small by comparison: clay preparation with a mixer, pug mill and extruder, the induced draught fan on a zigzag kiln, water pumps, and lighting. The induced draught fan is usually the main continuous consumer and it is modest next to a ceramics plant's fan load.
For a seasonal brick operation, model both firing and idle months. Confirm that there is an eligible, energised connection and approved export arrangement before counting net-metering credit. Apply the current credit and settlement rules rather than assuming unused energy is either worthless or worth the retail rate.
The second is that most brickfields have no building with a roof capable of carrying an array. The realistic option is a ground mount on the yard, and the yard is where green bricks are stacked and where trucks and trolleys move. Land use, not structure, is the constraint, and it needs settling with the operations manager rather than the accountant.
Both industries generate a soiling load that is worse than ordinary ambient dust, and in different ways.
Ceramics dust from body preparation, spray drying, pressing and glaze handling is fine, and a good deal of it is abrasive. Two rules follow from that. Never dry-wipe a module on a ceramics site, because dragging abrasive particles across glass with a cloth scratches it and a scratched module stays scratched for the rest of its life. And clean often enough that the deposit does not get wetted by dew and set, because a fine ceramic or glaze dust that has been damp and dried again behaves like a thin cement and needs far more work to remove.
Brickfield soiling is coal ash and clay, plus whatever the stack is emitting. Ash is alkaline, and wetted by dew it forms a film that rain does not clear. An array at a brickfield will need a cleaning regime through the firing season that most standard maintenance contracts do not budget for. That belongs in the contract at signing, priced against the actual site, rather than discovered in the first February.
On placement, the rule in both cases is the same: keep the array upwind of the stack and out of the plume, using the prevailing wind rather than an average of the whole year. Where the site geometry makes that impossible, accept the shorter cleaning interval and write it into the maintenance schedule.
Assess the kiln-hall roof carefully: heat, exhaust deposits and the temperature ratings of modules, cabling and mounting components can affect suitability. It is not automatically unusable, but it should be compared with cooler, cleaner roofs.
Compare the warehouse, packing hall, raw-material store and administration roofs using structural condition, temperature, soiling, shading and cable-route evidence. Do not assume that a roof is structurally suitable because its process is cooler.
Two structural points that catch people out on this kind of plant. Ball mills and presses put vibration into the building, and vibration relaxes fasteners over time, so specify locking hardware and follow the approved fastener inspection and maintenance schedule rather than only at the annual visit. And check whether the roof structure you are eyeing is tied into a crane runway, because a column and truss line carrying crane loads is not a line to add loading to without an engineer's assessment.
Before asking anybody for a quotation, get a month of interval data from the plant's HT meter and mark on it when the kiln fans, the ball mills, the spray dryer and the compressors run. That one chart will tell you more about whether a solar plant is worth building on this site than any generic feasibility report will, and any EPC contractor worth hiring will ask you for it before quoting a capacity.
Consult the relevant edition and the documents for the exact equipment and site: SREDA: Net Metering Guidelines and current application documents; IEA PVPS: operation and maintenance in different climates; JinkoSolar: model datasheets, certificates, installation manuals and warranties.
Share your application, equipment requirements and procurement timeline. Our engineers can help clarify the configuration and scope for your enquiry.