GridLightA traffic light for your electricity
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–your price now
–grid CO₂
–until next change
–green window
Checking the CAISO live feed…

Your day at a glance

Green cheap and clean Amber cheap but dirty Amber, hatched part-peak price Red peak price
Your price (¢/kWh, all-in, ≈ PG&E bundled rates from Mar 1, 2026)
Grid carbon (g CO₂/kWh, CAISO)

What will this cost?

Pick an appliance. GridLight finds the start time that minimises your bill plus the carbon, valued at the price you choose, on your plan.

$100/t CO₂
Edit to match your appliance.

Bill X-ray

Drop the hourly usage file every PG&E customer can download (Green Button: pge.com → Energy Usage Details → Green Button → Download my data). GridLight shows when your kWh happen, what shifting is worth, and which rate plan fits.

Processed in your browser. Nothing is uploaded.
or drag and drop a CSV here

Nudges at the right moment

People don't open energy apps. GridLight comes to them: a text before the peak, a heads-up when cheap power is dirty, and the green windows in their calendar.

  1. Plan-aware. Messages follow the customer's own rate plan and the season's prices, not generic "avoid 4–9 PM" advice.
  2. Carbon-aware. When off-peak power is dirty (overnight, gas and imports on the margin), GridLight says so and points to the cleaner midday window at the same price.
  3. One tap to act. Add today's green windows to your calendar, or let a smart charger or thermostat follow them.

How GridLight works, and what's real

Real

  • Rate plans, periods and all-in prices: PG&E residential pricing effective March 1, 2026 (E-TOU-C, E-TOU-D, EV2-A, E-ELEC). SVCE GreenStart average bills are within 0.3% of PG&E's on E-TOU-C (PG&E rate comparison, Mar 2026); per-period SVCE prices (SVCE generation + PG&E delivery + PCIA) differ slightly. Swapping in SVCE's own rate table is a data change.
  • Grid carbon: computed from CAISO Today's Outlook CO₂-by-source and demand files: winter = mean of Oct 16, 19, 22, 2026; summer = Jul 15, 2026. The app also tries CAISO's live feed.
  • Green Button CSV parsing, cost, CO₂, shift and plan-fit math, calendar export: all working code.

Simulated or simplified

  • The sample household is synthetic (labelled everywhere).
  • Carbon uses average grid intensity by hour; marginal emissions (what a shifted kWh actually changes) are typically even more favourable to midday shifting. Next step: WattTime marginal signal.
  • SVCE GreenStart is carbon-free on an annual accounting basis. GridLight uses hourly CAISO system emissions, because that is what the timing of a kWh changes (and what 24/7 clean-energy matching measures).
  • SMS delivery is a preview; energy charges exclude fixed charges, taxes and credits.

Traffic-light rule

Red = peak period of your plan. Hatched amber = part-peak. Amber = off-peak hours whose grid carbon sits in the dirtiest 60% of the day's range. Green = off-peak and clean. Best start times minimise bill + CO₂ × the carbon value you set ($100/t by default), within the window you choose.