Compare schemes

This page puts two to four schemes side by side and recomputes the comparison metrics live instead of copying the numbers stored with each scheme. For every selected scheme it rebuilds the topology from the saved configuration, solves the load flow and runs the full evaluation study, then reports sixteen rows: transformer rating, connected load, indicative price, number of sources, secondary tier, minimum bus voltage, network loss and loss percentage, transformer loading, annual loss cost, annual energy bill, optimal storage size, storage payback, grounding resistance against its target, low-voltage short-circuit current, 25-year life-cycle cost present value and the count of applicable grid-code items. The schemes are read from the scheme library, and the page also offers to freeze the current A/B reading pair into a signed snapshot with the usual three expiry options.

A proposal is decided by comparison, and the usual failure is comparing stale numbers: one scheme was saved before a capacity change, another before a tariff update. Recomputing every scheme through the same engine, with the same run conditions and the same evaluation inputs, turns the table into a like-for-like decision - and the difference rows then show which change actually bought the improvement.

Input = the identifiers of two to four schemes in the query string. Chain: for each scheme the page reads the saved configuration from the scheme library, rebuilds the topology from that configuration, then runs the load flow and the full evaluation study in parallel and keeps both results; the rows are then read from those two results (minimum voltage and network loss from the load flow, transformer loading, annual loss cost, annual bill, optimal storage, payback, grounding, fault current, life-cycle cost and grid-code count from the evaluation study). Output = the sixteen-row table with one column per scheme, and optionally a frozen A/B snapshot with a signed link. Linkage: the rows are not independent - a larger transformer lowers the loading and the loss but raises the price and the life-cycle cost, so the same scheme appears in several rows and the comparison is exactly the trade-off the buyer has to make; the snapshot freezes the current reading pair, so later scheme edits cannot change what was sent.