Octopus Agile Explained: How Half-Hourly Electricity Pricing Works
Octopus Agile is unlike any traditional electricity tariff. Instead of a single unit rate that stays the same all day, Agile updates its prices every 30 minutes — with tomorrow's prices published each afternoon for the full 24-hour period.
For consumers willing to shift flexible loads (EV charging, washing machines, batteries, heat pumps) to cheaper periods, the savings can be substantial. This guide explains exactly how the tariff works, when prices are lowest, and how to use GB Power Insights to plan your usage.
How Agile Prices Are Set
Octopus Agile prices are derived from the day-ahead wholesale electricity market (N2EX and EPEX Spot) — the same market where large generators and suppliers trade electricity in half-hourly blocks for the following day.
The process:
- Day-ahead market prices are published each afternoon for the following day's 48 half-hour periods
- Octopus applies a margin and standing charge, then passes the wholesale price through to customers
- Prices are published on the Octopus website, via API, and in the Octopus app around 4–5pm each day for the following day
This means wholesale electricity prices — which reflect the balance of supply and demand on the grid — directly determine what you pay. When wind is abundant and demand is low, prices drop. When demand peaks and gas plants are running at full capacity, prices spike.
You can see live and upcoming Agile prices on the Market Prices dashboard.
When Agile Prices Are Cheapest
Agile prices are lowest when three conditions align:
- High renewable generation (lots of wind or solar)
- Low demand (overnight, mild weather, off-peak)
- Low import prices (interconnectors carrying cheap European power)
Overnight: The Reliable Low
The most consistently cheap Agile window is 11pm–6am. Electricity demand drops by 20–30% overnight, and any wind generation still running isn't competing with high demand. Overnight Agile prices in 2025 typically ranged from 5–15p/kWh — compared to 25–35p/kWh at peak.
On very windy nights, overnight prices can drop to 1–5p/kWh, and occasionally go negative — Octopus pays you to consume electricity because there's a surplus of wind that would otherwise require wind farms to be curtailed.
Midday: The Solar Dip (Spring/Summer)
From March to September, solar output causes a visible dip in Agile prices between 10am and 2pm. With 10–13 GW of solar on the system, supply exceeds demand in this window and prices drop. Typical midday Agile prices on a sunny summer day: 8–15p/kWh.
Windy Periods: Any Time
On a highly windy day — and Great Britain experiences many — Agile prices can be low throughout the day, not just overnight. Wind output of 15+ GW pushes prices down to 5–12p/kWh even during normally expensive periods.
When Agile Prices Are Most Expensive
Agile prices spike during winter weekday evenings, 4–8pm:
- Demand peaks at 35–40 GW nationally
- Solar is zero (dark in winter)
- Gas peaking plants run at full capacity
- Prices can reach 40–80p/kWh, occasionally higher during cold snaps
During extreme winter events (e.g. Storm Arwen-style periods, cold anticyclones), Agile prices have spiked above £1/kWh. This is rare but not unknown.
The Agile price cap (currently 100p/kWh) limits the maximum customers pay per unit, but even half that is expensive electricity. Avoiding consumption during peak windows is the single most important Agile strategy.
Price Distribution: What to Expect
Based on 2025 data, approximate Agile price distribution:
| Price range | Typical occurrence | Best use |
|---|---|---|
| Negative to 2p | Windy overnight (rare) | Charge everything you can |
| 2–10p | Windy overnight / high wind days | EV, battery charging |
| 10–18p | Overnight, midday solar | General household use |
| 18–28p | Typical daytime | Normal consumption |
| 28–40p | Morning/evening shoulder | Reduce flexible loads |
| 40p+ | Peak winter evenings | Discharge battery, avoid grid |
The Agile-Carbon Relationship
Agile prices and carbon intensity are strongly correlated — because the same underlying factor (renewable generation vs. gas generation) drives both:
- Low price + low carbon: Wind/solar abundant → cheapest and greenest
- High price + high carbon: Gas-heavy grid → expensive and dirty
This means optimising for Agile prices usually also optimises for carbon. The Market Prices view shows both Agile prices and carbon intensity together, so you can see whether the cheapest window is also the greenest (usually yes).
The main exception: imports via interconnectors from France (nuclear-heavy, low-carbon but not renewable) can lower prices without being particularly low-carbon from a pure wind/solar perspective.
Who Benefits Most From Agile?
Agile delivers the most savings to households with flexible large loads:
High benefit:
- EV owners who can schedule overnight charging
- Home battery owners who can arbitrage cheap/expensive windows
- Heat pump owners willing to pre-heat during cheap periods
- Work-from-home households with flexible appliance use
Moderate benefit:
- Households with standard usage patterns who can shift dishwasher/washing machine to overnight
- People who can manually shift cooking and hot water
Agile may not suit:
- High-consumption households on fixed schedules where peak avoidance is impractical
- Those who find price volatility stressful or confusing
- Homes without any flexible loads
Automating Agile Optimisation
The most effective Agile users automate their flexible loads:
- EV smart chargers (Ohme, Indra, Zappi with Agile): Read tomorrow's prices automatically and charge during the cheapest slots overnight
- Home batteries (GivEnergy with GivTCP, Powerwall with Home Assistant): Schedule charging to the overnight low and discharging during the evening high
- Heat pumps: Schedule pre-heating to start during cheap morning or midday windows
- Immersion heaters with Eddi/Shelly: Set to operate during sub-10p windows
Several third-party apps (Octopus Energy app, Charge HQ, Tesla app, GivTCP) read Agile prices via API and automate scheduling. Manual checking works too — Octopus sends tomorrow's prices at 4pm by notification.
Summary
- Agile prices update every 30 minutes, based on wholesale market prices published at 4–5pm daily
- Cheapest windows: 11pm–6am overnight, and midday solar dip March–September
- Most expensive: Winter weekday evenings 4–8pm (can reach 40–80p/kWh)
- Agile price and carbon intensity are closely correlated — optimising one usually optimises both
- Most value for households with EVs, batteries, or heat pumps that can be scheduled
- The Market Prices dashboard shows live and upcoming Agile prices alongside carbon data