PEak Saver: understanding time-of-use electricity pricing

PEak Saver is PE’s time-of-use electricity tariff, designed to help businesses better understand when electricity costs more – and how shifting flexible usage to lower-demand periods can help manage energy spend.

Unlike flat-rate tariffs, time-of-use pricing reflects how the electricity system actually operates: costs vary throughout the day depending on demand across the grid.

By aligning electricity usage with off-peak periods, businesses may be able to reduce exposure to higher system charges, while supporting a more efficient and resilient energy network. 

How time-of-use pricing works

Electricity prices are influenced by demand on the national and regional networks. When demand is high, typically during weekday peak hours, the cost of generating, transmitting and distributing electricity increases.

Time-of-use tariffs reflect these variations by applying different prices at different times of day, rather than a single flat rate.

You can explore the wider context here:

• Ofgem: How energy prices are set
  https://www.ofgem.gov.uk/information-consumers/energy-advice-households/understanding-energy-prices

• National Grid ESO: Balancing supply and demand
  https://www.nationalgrideso.com/balancing-energy-system

👉 For an overview of how PE structures pricing, visit How our tariffs work

 

How PEak Saver supports cost management

PEak Saver uses a Red, Amber and Green traffic-light pricing structure, based on industry charges:

• 🟢 Green – off-peak periods, when demand and system costs are lower

• 🟠 Amber – moderate demand periods

• 🔴 Red – peak demand periods, when system costs are highest

This structure is designed to make it clearer when electricity is typically more expensive, enabling businesses to plan and shift flexible usage where operationally possible.

👉 See pricing periods for your distribution area

 

What types of usage can be shifted?

Every business is different, but electricity use that is often more flexible includes:

• EV charging

• Refrigeration or defrost cycles

• Battery or plant charging

• Cleaning, processing or manufacturing runs

• IT equipment, servers or backup systems

• Back-office or non-essential operations

Even partial shifts, rather than complete changes, can help reduce exposure to peak-period pricing.

 

Using data to inform decisions

PEak Saver is supported by PE’s Enfiniti portal, which allows customers to view electricity consumption in near real time.

The portal visualises usage against tariff time slots, helping businesses to:

• Understand when electricity is being used

• See how consumption aligns with pricing periods

• Identify opportunities to shift flexible demand

• Monitor trends across single or multiple sites

This data-led approach supports informed decision-making rather than assumption-based changes.

👉 Learn more about Enfiniti: PE’s customer portal

 

 Why pricing periods vary by location

Electricity distribution costs differ across the UK depending on regional infrastructure and network demand. For this reason, time-of-use pricing periods vary by Distribution Network Operator (DNO) area.

Customers can find details of their local distribution area and pricing periods via PE, or learn more about DNO regions here:

• Energy Networks Association – Who is my network operator?
  https://www.energynetworks.org/customers/find-my-network-operator

 

Supporting a more efficient energy system

By encouraging electricity use outside peak demand periods, time-of-use tariffs help:

• Reduce strain on the electricity network

• Support grid stability

• Enable more efficient use of generation assets

• Complement the transition to a lower-carbon energy system

Further reading:

• Ofgem – Flexibility and smart energy use
  https://www.ofgem.gov.uk/energy-policy-and-regulation/policy-and-regulatory-programmes/flexibility

• National Grid ESO – Future energy system
  https://www.nationalgrideso.com/future-energy

 

Is PEak saver right for your business?

PEak Saver is designed for businesses that have some flexibility in when electricity is used. It does not require reducing output or service levels, but it does rely on understanding usage patterns and making informed operational choices.

👉 Find pricing periods for your distribution area
👉 Speak to our team to understand suitability for your business
👉 Explore all PE business solutions