WHY · Project

Open-Source Toolkit That Predicts How Households Actually Use Energy

energyTestedTRL 5Thin data (2/5)

why-h2020.eu

Imagine trying to plan a city's electricity grid but having no idea when people will turn on their heaters, charge their cars, or cook dinner. Traditional energy models treat all households the same — which is like predicting traffic without knowing where people live or work. The WHY project built software that figures out why households use energy the way they do, accounting for things like income, building type, and daily habits. It plugs directly into the big energy planning models that governments and utilities already use, giving them much sharper demand forecasts.

By the numbers

consortium partners across 5 countries

total project deliverables produced

open-source software deliverables (toolkit, plugins, libraries)

major energy system models integrated (PRIMES, TIMES)

The business problem

What needed solving

Energy utilities, grid operators, and policy makers cannot accurately forecast residential energy demand because traditional models ignore the diversity of households — different building types, incomes, family sizes, and daily habits all drive wildly different consumption patterns. This leads to over-provisioned grids, poorly designed tariffs, and energy efficiency policies that look good on paper but miss their targets in practice.

The solution

What was built

An open-source WHY Toolkit with plugins and libraries that uses causal modeling to forecast residential energy demand based on actual household behavior. The software integrates directly with PRIMES and TIMES energy system models, comes with user manuals and video tutorials, and supports both short-term load forecasting and long-term policy impact assessment.

Audience

Who needs this

Distribution System Operators (DSOs) planning grid capacity and load balancingEnergy retailers designing demand-response and time-of-use tariff programsPolicy consultancies evaluating energy efficiency regulations for governmentsMunicipal energy planners forecasting demand for district heating or smart city projectsEnergy system modelers who already use PRIMES or TIMES and need better demand-side accuracy

Business applications

Who can put this to work

Energy Distribution

enterprise

Target: Distribution System Operators (DSOs) managing local grids

If you are a DSO struggling to balance supply and demand across diverse residential areas — this project developed an open-source toolkit with plugins for PRIMES and TIMES energy models that forecasts household energy demand by accounting for dwelling types, income levels, and behavioral patterns. The WHY Toolkit, delivered with user manuals and video tutorials, lets you run scenarios to see how policy changes or new tariffs would shift consumption across your network.

Energy Retail

mid-size

Target: Energy retailers designing tariff and demand-response programs

If you are an energy retailer trying to design pricing plans or demand-response programs but your customer segmentation is too coarse — this project created load forecasting tools that categorize households into distinct consumption profiles. The open-source WHY libraries let you simulate how different customer segments react to interventions like time-of-use pricing, helping you design programs that actually change behavior instead of guessing.

Energy Policy Consulting

any

Target: Consultancies advising governments on energy efficiency policy

If you are a consulting firm hired to evaluate whether a proposed building efficiency regulation will actually reduce energy demand — this project built causal modeling software that performs both ex-ante and ex-post policy assessment. The WHY Toolkit integrates with PRIMES and TIMES, the same models the European Commission uses, so your analysis speaks the same language as the regulators you advise.

Frequently asked

Quick answers

What would it cost to adopt the WHY Toolkit?

The WHY Toolkit, plugins, and libraries are all open-source, so there is no licensing cost. Your investment would be in integration effort — connecting the toolkit to your existing energy system models and training your analysts to use it. Budget data for the project itself is not available in the dataset.

Can this work at the scale of a national energy grid?

The toolkit was designed to integrate with PRIMES and TIMES, which are the energy system models used for EU-wide and national-level energy planning. Test simulations were carried out and documented in the deliverables. Scaling to your specific grid would depend on the granularity of your household data.

Who owns the intellectual property? Can I use it commercially?

All results were open-sourced to maximize uptake, as stated in the project objectives. The 3 demo deliverables (WHY Toolkit, WHY Plugins, WHY Toolkit Libraries) are all described as open-source software implementations. You should verify the specific open-source license on the project website at why-h2020.eu.

How does this integrate with systems we already use?

The WHY Plugins were specifically built to integrate with PRIMES and TIMES energy system models, which are widely used across Europe. The plugin deliverable includes a user manual and practical integration examples. If you use other energy system models, the open-source architecture allows custom adaptation.

What evidence is there that the forecasts are accurate?

The WHY Toolkit deliverable includes results of test simulations that were peer-reviewed by scientific experts. The project used causal modeling rather than simple correlation, which means the forecasts account for cause-and-effect relationships in energy consumption. However, based on available project data, real-world validation at commercial scale is not documented.

Is this compliant with EU energy regulations?

The project was funded under topic LC-SC3-EE-14 (energy efficiency) and explicitly targets EU policy assessment. The toolkit supports both ex-ante and ex-post evaluation of policy measures, aligning with how the European Commission evaluates energy efficiency directives. The integration with PRIMES — the Commission's own modeling tool — further supports regulatory alignment.

Consortium

Who built it

The consortium of 9 partners across 5 countries (Austria, Germany, Greece, Spain, Netherlands) is heavily research-oriented, with 4 research organizations and only 1 industry partner — an 11% industry ratio. The coordinator is Universidad de Deusto in Spain, a university rather than an industry player. Two SMEs participate, adding some commercial sensitivity. For a business considering this toolkit, the low industry involvement means the software was built by researchers for energy modelers, not packaged as a commercial product. The upside: the open-source release and PRIMES/TIMES integration mean you can adopt it without going through a vendor. The risk: you may need in-house technical talent to deploy and maintain it.

UNIVERSIDAD DE LA IGLESIA DE DEUSTO ENTIDAD RELIGIOSACoordinator · ES
KLIMA-BUNDNIS DER EUROPAISCHEN STADTE MIT INDIGENEN VOLKERN DER REGENWALDER / ALIANZA DEL CLIMA EVparticipant · DE
FUNDACION DEUSTO-DEUSTU FUNDAZIOAthirdparty · ES
FORSCHUNGSZENTRUM JULICH GMBHparticipant · DE
NEDERLANDSE ORGANISATIE VOOR TOEGEPAST NATUURWETENSCHAPPELIJK ONDERZOEK TNOparticipant · NL
E3-MODELLING AEparticipant · EL
RENEWABLES GRID INITIATIVE EVparticipant · DE
GOIENER S.COOPparticipant · ES
4WARD ENERGY RESEARCH GMBHparticipant · AT

How to reach the team

Universidad de Deusto, Bilbao, Spain — contact via SciTransfer for a facilitated introduction to the research team

Order a report on this consortium See UNIVERSIDAD DE LA IGLESIA DE DEUSTO ENTIDAD RELIGIOSA profile →

Next steps

Talk to the team behind this work.

Want to know if the WHY Toolkit fits your grid planning or policy assessment needs? SciTransfer can arrange a technical briefing with the development team and help you evaluate integration with your existing energy models.

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