Joulen: Optimisation and market trading for flexible energy assets

Joulen combines asset forecasting, dispatch and energy trading through Flex, Trade and Grid services for distributed and larger battery portfolios.

Summary

Best for
Installers, energy suppliers, aggregators and battery developers seeking a route into flexibility markets.
Less suited to
A standalone energy meter or guaranteed revenue estimate independent of tariff and market conditions.
Deployment
Connected asset portfolios with forecasting, optimisation, dispatch and market execution services.
Data in
Asset availability, operating constraints, generation, demand, tariffs and market signals.
Pricing
Commercial terms depend on the service and assets; published revenue estimates are indicative rather than guaranteed.

Overview

Joulen combines software optimisation with energy-market execution. It forecasts generation, demand and market value, then decides how flexible assets should charge, hold energy or export. The company description places that activity across home batteries, commercial storage, electric vehicles and larger installations, working through installers, retailers and equipment manufacturers. This is an operational service rather than simply a dashboard: its value depends on both the site's physical flexibility and the ability to trade it. Joulen describes a repeating analysis, optimisation and control cycle, supported by an in-house trading team.

Offering

The current offering has three distinct routes. Flex combines optimisation and market participation for partners adding flexibility to their customer proposition. Trade serves aggregators and HEMS or EMS providers that need market access and trading execution while retaining their existing platform role. Grid addresses standalone and co-located larger batteries, combining dispatch with revenue opportunities across markets. This separation is useful because a residential installer does not need the same operating model as a grid-scale asset owner. The services share optimisation capabilities but address different responsibilities in the energy value chain.

Products and platforms

  1. Joulen Flex

    Flexibility service

    Combined asset optimisation, market participation and trading for partner portfolios.3

  2. Joulen Trade

    Energy trading service

    Market-access and execution service for aggregators and HEMS/EMS providers.2

  3. Joulen Grid

    Grid-scale battery optimisation

    Forecasting, dispatch and trading for standalone and co-located battery assets.6

Technology

Joulen Trade describes accredited Virtual Lead Party and Virtual Trading Party capabilities alongside its trading infrastructure. Its Grid service combines forecasting with asset dispatch and a portal that explains revenue by market and trading rationale. These functions depend on asset availability and operating constraints as well as price signals. The homepage names hardware and platform integrations, including Fox ESS, SolaX, Solis, Growatt and Sigenergy, but that is not a model-level compatibility register or a public protocol specification. A partner integration therefore needs the supported equipment and control path established for the particular portfolio.

Markets

Flex targets installers, energy companies, manufacturers and growing portfolios, bringing optimisation and trading together without each partner building a trading desk. Its published calculator explicitly treats projected revenue as indicative and dependent on site, tariff and market conditions. Trade instead lets an existing aggregator or energy platform use Joulen's market infrastructure, while Grid addresses the operating strategy of larger batteries. These distinctions help an owner compare service scope: reducing behind-the-meter costs, selling aggregated flexibility and dispatching a grid-connected storage plant involve different obligations and sources of value.

Company

Joulen's company background records its founding in 2017 and Belfast headquarters. A July 2024 announcement documents the rebrand from The Electric Storage Company to Joulen and describes international growth around the PARIS software platform. The current privacy notice identifies the legal business as Power On Technologies Limited trading as Joulen, company NI643146. Its leadership page gives Belfast and London locations and names Chris Doherty as chief executive. The present Flex, Trade and Grid propositions therefore sit within an established business and legal identity, rather than a separate newly created company.

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References

  1. Joulen: Your Energy. Maximised. (opens in a new tab)
  2. Trade: market access & trading (opens in a new tab)
  3. Flex: complete flexibility as a service (opens in a new tab)
  4. Joulen technical document (opens in a new tab) (PDF)
  5. The Electric Storage Company announces rebranding to Joulen and leadership team appointments – Joulen (opens in a new tab)
  6. Joulen Grid: maximise the return on your energy assets (opens in a new tab)
  7. Privacy Notice | Joulen (opens in a new tab)
  8. About Joulen (opens in a new tab)

This profile does not imply a commercial relationship with Joulen and may contain inaccuracies.