How It Works

How Do Power Markets Work?

Electricity prices are set every 5 minutes at thousands of locations across the US. Grid operators called ISOs calculate these prices based on how much power is needed and what it costs to produce. Prices vary by location — when transmission lines are overloaded, some areas pay much more than others.

OnPeak currently covers three nodes: New York City, Boston, and Northern California, each in a different ISO.

What Is the Day-Ahead Market (DAM)?

Every day, the ISO publishes 24 hourly prices for the next day — one price per hour, per node. These are set the day before through a bidding process between generators and utilities. Think of DAM prices as the market's best expectation of what power will cost tomorrow.

What Are Real-Time (RT) Prices?

RT prices are what power actually costs, updated every 5 minutes as conditions change on the grid. Weather shifts, generator outages, or demand surprises can push RT prices far above or below what the DAM expected.

How Do Contracts Work?

When DAM prices are released, contracts go live for each node. Each contract asks one question:

Will the average RT price for the day beat the DAM price?

The DAM price is the "line." At the end of the day, we average all 288 five-minute RT prices. If the RT average is higher than the DAM line, the contract settles Yes. If lower, No.

DAM release times (when contracts go live):

  • NYC & Boston: 11:00 AM ET
  • Northern California: 4:00 PM ET

You can trade on the market pages or from the live map.

FAQ

What is an ISO?

An Independent System Operator — a nonprofit that runs the electric grid and market for a region. They don't own power plants; they coordinate who generates, how much, and at what price. The US has seven: NYISO, ISO-NE, PJM, MISO, SPP, ERCOT, and CAISO.

Why do prices go negative?

When there's more power being generated than anyone needs — usually from solar or wind that can't easily shut off — generators actually pay the market to take their output. It's cheaper than turning off and restarting.

What causes price spikes?

  • NYC: Transmission congestion. The city sits behind constrained power lines, so when demand surges (summer AC), expensive local generators set the price.
  • Boston: Winter gas shortages. Limited pipeline capacity means heating and power plants compete for the same gas, driving prices up during cold snaps.
  • NorCal: The solar rollercoaster. Midday solar floods the grid (sometimes pushing prices negative), then drops off in the evening right as demand peaks, forcing expensive gas plants online fast.

This is early

OnPeak is still early and there's a lot left to build. If you have feedback, a feature idea you think would be cool, or a market you'd like to see added, feel free to email us at onpeakmarket@protonmail.com. We read and respond to everything.