Top 10 Best Energy Efficiency Software of 2026

EnergyPlus is a state-of-the-art, open-source whole-building energy simulation engine developed by the U.S. Department of Energy for modeling heating, cooling, lighting, ventilation, and energy flows as well as water in buildings. It enables detailed analysis of energy efficiency, HVAC system performance, indoor air quality, and renewable energy integration through physics-based calculations. Widely used for new construction, retrofits, and research, it supports standards compliance like ASHRAE 90.1 and LEED certification.

OpenStudio is an open-source, cross-platform software platform developed by NREL for whole-building energy modeling and simulation. It integrates with EnergyPlus to create detailed models of building energy use, supporting analysis for energy efficiency, code compliance (e.g., ASHRAE 90.1), and green building certifications like LEED. Users can build models graphically via SketchUp plugin or programmatically, apply measures for optimization, and run parametric analyses.

DesignBuilder is a comprehensive building energy modeling software that provides an intuitive graphical user interface built on the industry-standard EnergyPlus simulation engine. It enables users to create detailed 3D models of buildings and perform dynamic simulations for energy use, thermal comfort, daylighting, and HVAC performance. The software supports regulatory compliance, sustainability certifications like LEED and BREEAM, and optimization for low-energy design strategies.

IES Virtual Environment (VE) is a comprehensive building performance simulation platform that enables dynamic modeling of energy consumption, thermal comfort, daylighting, airflow, and acoustics across entire building lifecycles. It integrates advanced simulation engines like Apache for whole-building analysis, supporting sustainable design, code compliance, and certification processes such as LEED and BREEAM. Widely used by architects and engineers, VE facilitates optimization from early concept design to detailed retrofitting.

eQUEST, available at doe2.com, is a free whole-building energy simulation program powered by the DOE-2 engine, enabling users to model hourly energy use, costs, and indoor comfort for commercial buildings. It supports detailed analysis of HVAC systems, lighting, envelopes, and renewables, with built-in compliance tools for standards like ASHRAE 90.1 and California Title 24. The CHEETAH wizard simplifies input for quick estimates, while allowing extensive customization for advanced simulations.

Cove.tool is a cloud-based platform designed for whole-building performance analysis, focusing on energy efficiency, daylighting, cost optimization, and embodied carbon emissions during early-stage design. It integrates with BIM tools like Revit and Rhino, providing real-time simulations and iterative feedback to architects, engineers, and developers. The software streamlines sustainability assessments, helping teams achieve high-performance buildings with data-driven decisions.

RETScreen Expert is a cloud-based software platform developed by Natural Resources Canada for conducting pre-feasibility and detailed analyses of renewable energy, cogeneration, and energy efficiency projects. It enables users to model energy production, savings, financial viability, and environmental impacts using validated engineering models and extensive databases. The tool supports a wide range of technologies including solar PV, wind, biomass, HVAC retrofits, and district energy systems.

TRACE 3D Plus is a whole-building energy modeling software from Trane Technologies, specialized in simulating HVAC systems, energy consumption, and building performance for commercial projects. It enables engineers to design, size, and optimize HVAC equipment while ensuring compliance with energy codes like ASHRAE 90.1 and Title 24. The tool features an intuitive 3D interface for geometry input, detailed load calculations, and scenario analysis to improve energy efficiency and reduce operational costs.

Carrier HAP (Hourly Analysis Program) is a desktop software solution from Carrier for detailed HVAC load calculations, annual energy simulations, and system sizing in commercial and institutional buildings. It models building geometry, internal loads, weather data, and HVAC equipment to predict peak loads and energy use over time, aiding in energy-efficient design and code compliance. HAP uses a DOE-2-based engine for accurate, hourly-by-hourly analysis and generates comprehensive reports for optimization.

Autodesk Insight is a cloud-based performance analysis tool integrated directly into Revit, enabling architects and engineers to conduct rapid energy modeling, daylighting analysis, and sustainability simulations during early design stages. It uses powerful cloud computing to run whole-building energy simulations based on standards like ASHRAE 90.1, allowing users to compare multiple design alternatives quickly and visualize performance metrics. The platform supports iterative optimization for factors like envelope, HVAC, and shading to improve energy efficiency and comfort.