Event-based upward flexibility in Great Britain

See analysis plan.

Between June and September 2025, we will run five “Turn-Up” events in partnership with Octopus Energy Limited (OE), with exact timing determined by market conditions. For each event, participating customers will be randomly assigned to one of five groups:
1. Control – no incentive is offered during the event.
2. 50% Discount – customers receive a 50% discount on their electricity usage (£/kWh) during the event window.
3. 100% Discount (Free Electricity) – customers pay nothing for electricity consumed during the event.
4. Free Electricity + Low Payment – in addition to receiving free electricity, customers are offered a small monetary payment (5p/kWh, approximately 25% of customers’ typical unit rate) for each kWh they turn up.
5. Free Electricity + High Payment – customers receive free electricity and a larger monetary payment (15p/kWh, approximately 75% of customers’ typical unit rate).

Customers will be randomized into a sequence of events such that each customer receives each of the five conditions (four treatments and one rotating control). More explanations about how these sequences are generated in the experimental design description below. In addition, we will include a separate group of customers who are never treated in any event; this pure control group will serve as a baseline for evaluating the effects of trial participation itself, independent of treatment exposure.

Those selected are automatically notified via email prior to each session, with instructions on the time window and the reward offered. They are encouraged to shift their electricity usage, such as running the washing machine, charging their electric vehicle, or heating water, into the designated session period. After each session, they receive a summary of their usage and rewards, which may include discounts, free electricity, or cash payments.

Sample: We will access a pool of 480,523 customers who:

1) Are not enrolled and have not been contacted for other Turn-ups campaigns, which include: NPG Power-ups, LCM Power-ups and UKPN Power-ups
2) Are not enrolled for the Free Electricity Octoplus campaign
3 Have a working smart meter that is sending at least half hourly meter readings
4) Are not on the Agile Octopus tariffs (these customers are already responding to half-hourly wholesale price signals, including negative wholesale prices)

We will hold 5 “Turn up” events during June through September 2025 – each event lasting 1 hour. These events will not happen on predetermined days – they will run when the price of the electricity in the day ahead market is close to 0 or negative.

2024-06-14

2024-09-14

Associated MPAN electricity consumption (import kWh only) at the half hourly level during “Turn up” events, in kWh

Consumption is measured at the customer meter point level.

Survey responses sent to all participating households (including identified pure control groups who never receive any outreach on the events). These include:
To what extent do you think that it is technically feasible to stop greenhouse gas emissions by the end of the century while [maintaining / sustaining] satisfactory standards of living in [country]?
Not at all; A little; Moderately; A lot; A great deal
If we decide to halt climate change through ambitious policies, to what extent do you think it would negatively affect your lifestyle?
Not at all; A little; Moderately; A lot; A great deal
Do you believe that Government climate policies will provide more benefits or impose more costs on you personally?
Mostly benefits; Neutral; mostly costs

These survey questions are designed to assess whether participation in the trial influences individuals' perceptions of the energy transition – specifically, whether it increases the likelihood that they view the transition as personally beneficial. The exact wording may be refined following piloting to ensure clarity, neutrality, and respondent comprehension.

See analysis plan.

See attached analysis plan for details.

Our primary research question is, how do financial incentives affect half-hourly electricity consumption (kWh) during “Turn-up” events? Specifically, this trial aims to quantify the causal impact of different incentive levels – a 50% discount, free electricity, and free electricity with two levels of additional payments – on customers’ short-term electricity usage during targeted event windows.

The primary analysis will estimate the overall treatment effects during Turn-up events by comparing each treatment group to a pooled control group. This pooled control includes both the rotating control group (assigned during each event) and the pure control group (which is never contacted and never treated).

Computer using R. See attached analysis plan for details.

Account number

Yes

60,000 clusters, where regressions are clustered at the customer account level

For 60,000 customers, each event includes two half-hour periods (i.e., one hour per event), with a total of 5 events. This results in approximately 600,000 observations in the main analysis, clustered at the customer level (60,000 clusters).

Treatment: 50,042 (among which 20% will be a "rotating control group" at any given event; see analysis plan for details)
Pure Control: 9,958

We conducted simple simulations of our trial design using consumption data from British Octopus Energy customers in 2024, assuming 10,000 customers per trial arm (ignoring the “pure control” group, which we believe makes our power calculations conservative). We created placebo treatment and control indicators, assuming five “events” between May and July 2024. Using the rule of 2.8 (wherein the MDES at 80% power and 5% alpha is 2.8 times the standard error on the treatment coefficient), we find that our MDES is 0.0168 kWh per hour (2.11% of hourly consumption during events).