OpenStudio is an open-source SDK (software development kit) for building energy simulation. OpenStudio greatly reduces the cost of developing end-use applications and services that exploit energy simulation by providing a large library of common helper functions for creating, querying, and transforming energy models, running simulations, and working with results. OpenStudio updates are released quarterly—the most recent version update, 1.9.0, was released 9/30/2015.

EnergyPeriscope is designed to speed up and enhance the sales process. Easily crunch the numbers, generate professional sales proposal materials, and manage your sales activities. Model and quote: PV, solar thermal, energy storage, energy efficiency, wind turbines.

Track, compare, target and evaluate the energy efficiency performance of your estate with advanced weather analytics and comparison benchmarking. View and share estate-wide energy performance reporting for total energy consumption, by period, fuel and building for monitoring and understanding your estate’s energy consumption.

EP-Quick creates input files for many different buildings using built in templates for the shape and zone layout.

FineHVAC is a powerful BIM application that integrates drawings & calculations within an intelligent, AutoCAD®-like environment. Fine HVAC’s Calculation module is closely interacting with the BIM model: it reads the physical properties of the BIM objects to calculate the HVAC loads space by space. Besides, it recognizes the networks and receptors to calculate the air-duct and piping networks, producing the necessary calculations, as well as the entire set of drawings (plan views, vertical diagrams, axonometric diagrams, 2D/3D Piping/Ducting Networks etc) properly updated with the calculation results.

BSIMAC's three main functions are: (a) calculation of the cooling/heating loads and the required capacities of HVAC equipment, (b) annual energy simulation of the building and HVAC equipment, and (c) calculation of the expected room (space) temperatures with no cooling or heating on summer and winter design days. These three functions require virtually the same input data. The computations are carried out on an hour-by-hour basis.

Free open-source library with dynamic simulation models for building and district energy and control systems

Group of CYPE programs for thermal and energy analysis of buildings. The applications that work with the 3D model of the building are integrated in the OPEN BIM workflow via the IFC4 standard.

EnergyPlus is DOE's whole-building energy simulation engine. EnergyPlus includes advanced simulation features including sub-hourly time steps, simultaneous solution of zone conditions and HVAC system actions, a modular HVAC structure that accommodates a wide range of system configurations, and a runtime scripting language for user-defined control strategies. Version 8.4.0 was released 9/30/2015. Learn more at energyplus.net.

TREAT is winner of the prestigious R&D 100 award and still the only energy audit software approved by the DOE for all residential housing types – including multifamily. TREAT is market tested, with thousands of users enjoying accurate results for over a decade of supporting whole house energy audits. TREAT 3.4 is RESNET accredited. With thorough building material libraries, single-family and multifamily versions, and the ability to project savings from combined retrofits, TREAT is a comprehensive and flexible software platform for your energy audit efforts. TREAT features onboard SUNREL energy modeling, dynamic links to local weather logs, a unique model “true-up” feature, and concise energy savings reports to ensure that projected energy savings are reliable and that contractors convert retrofit sales with every house call.