Buildings in cities consume 30 to 70% of the cities' total primary energy.
Retrofitting the existing building stock to improve energy efficiency and reduce energy use is a key strategy
for cities to reduce green-house-gas emissions and mitigate climate change. Planning and evaluating retrofit
strategies for buildings requires a deep understanding of the physical characteristics, operating patterns,
and energy use of the building stock. This is a challenge for city managers as data and tools are limited and
City Building Energy Saver (CityBES) is a web-based data and computing platform, focusing
on energy modeling and analysis of a city's building stock to support district or city-scale efficiency programs.
CityBES uses an international open data standard, CityGML, to represent and exchange 3D city models. CityBES
employs EnergyPlus to simulate building energy use and savings from energy efficient retrofits. CityBES provides
a suite of features for urban planners, city energy managers, building owners, utilities, energy consultants and
The following figure shows the three layers of the software architecture of CityBES:
the Data layer, the Algorithms and Software layer, and the Use Cases layer. The Data layer includes the weather
data, and the CityGML 3D city model. The Software layer includes EnergyPlus, OpenStudio and CityBES. The Use
Cases layer provides examples of potential applications, including energy benchmarking, urban energy planning,
energy retrofit analysis, building operation improvement, as well as performance visualization.
CityBES also generates load profiles for buildings in an urban district, using the USDOE
Commercial Prototype Building Models and the and the
Commercial Reference Buildings.
The load profiles include cooling loads, heating loads, domestic hot water loads, and electrical loads for fans
and pumps. The load profiles can be used in sizing and simulation of performance of district heating and cooling
CityBES: A Web-based Platform to Support City-Scale Building Energy Efficiency.
Urban Computing 2016. PDF
City-Scale Building Retrofit Analysis: A Case Study using CityBES.
Building Simulation 2017. PDF
CityBES is sponsored by Lawrence Berkeley National Lab, under the Laboratory
Directed Research and Development (
Start an Analysis
Please start an analysis by selecting a building dataset.
Manage Building Datasets
The City Building Energy Saver (CityBES) is developed by a team led by
Tianzhen Hong (firstname.lastname@example.org) at LBNL.
Researchers at LBNL:
Tianzhen Hong, Ph.D. (PI)
Yixing Chen, Ph.D. (Lead Programmer)
Mary Ann Piette, Director of Building Technology and Urban Systems Division
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