Real tariffs, bill check, demand charges and tax benefits

SurgePV finds the utilities for the site address: PG&E serves it, SMUD is nearby. It lists PG&E's commercial rates with structure badges, source and version, and suggests B-19 Secondary from the site's 512 kW peak.

The whole rate on one page: when each period applies in summer and winter, energy $/kWh, the two demand charges in $/kW, the customer charge, the export rule and the yearly escalation, with the version and source.

Type in last month's bill and SurgePV rebuilds it line by line on B-19: $55,547.40 against the real $54,405.00, within 2.1%. Demand matches the bill to the kW; the small gap is in energy and the screen says why.

When the copy of a bill is far off, SurgePV says so and ranks the likely causes with their dollar size. Here the rate version from the US rate database lacks B-19's peak-period demand charge; one click switches to the tariff-sheet version.

A year of 15-minute PG&E data replaces the estimated warehouse profile. Both pass the bill check, but the meter shows the peaks at 06:30 and 18:15, when solar is small. The estimate would have promised $15,980 a year of demand savings; the meter says $11,430.

Twelve rebuilt bills before and after solar. Year-1 savings of $322,670 split into energy ($311,240, including export credits) and demand ($11,430). After solar, 61% of the bill is demand charges.

Each month's highest 15 minutes before and after solar, and the demand charge it sets. Solar takes 22 to 51 kW off the monthly peak because Rivergate's peaks come when solar is small.

A what-if, kept out of the proposal: a 150 kW / 400 kWh battery that holds grid import under 380 kW saves $16,333 a year more in demand charges and pays back in 6.4 years on its own. One click adds it as option B.

On Pricing, MACRS 5-year plus 40% bonus on a $1,887,000 basis (cost less half the 30% ITC) at a 28% tax rate saves $528,360 over 6 years and brings payback from 4.8 to 3.4 years. The checks for commercial, cash or loan and country are shown.

What Rivergate's facilities lead reads: the PG&E bill today and with solar, month by month, with demand charges on their own line and a plain note on why solar lowers them only a little.

The tax page: ITC, depreciation by year and payback with and without tax savings, with the tax-advisor line. Below it, every assumption, including the rate's version and source and the bill check.

A second Rivergate site in Portola is served by Plumas-Sierra REC, which has no rates in the library. The designer can enter the rate with a demand charge now, and send the rate sheet so SurgePV adds the co-op for everyone.

PG&E's Oct 2026 B-19 arrived after proposal v3 went out on the Mar 2026 version. SurgePV shows what changed and what it does to savings and payback, and pauses Send and Share until the designer keeps the old version or makes v4.

The first PG&E file was the wrong export: meter register readings, and only 212 days. SurgePV lists every problem at once in plain words, says how to get the right file, and saves nothing until it is fixed.

Foothills Cold Storage in Calgary (CA$). Alberta splits the wire owner from the retailer, bills demand per kW per day and applies a 90% ratchet. The bill reproduces within 1.5%, and the ratchet holds year-1 demand savings to CA$9,272 against CA$11,106 from year 2.

Parekh Textiles on Torrent Power HTP-I. Demand is billed in kVA with an 85% contract-demand floor, plus FPPPA, peak-hour charge, night rebate and 15% duty. The bill reproduces within 1.4%; the gap is the power-factor rebate.

The same Tax benefits panel for an Indian company: 40% written-down value, half rate in year 1 because commissioning is in February, at 25.17% tax. Payback goes from 3.2 to 2.7 years.

Empacadora San Juan in Querétaro on CFE GDMTH: base, intermedia and punta energy, a distribution charge and a capacity charge. The bill reproduces within 1.5%. Punta falls after sunset, so solar saves energy and some distribution, not capacity.