EnergyPlus Version 3.0 Available
The latest release of the EnergyPlus building energy simulation program,
Version 3.0, was completed on November 13, 2008 and is now available in
versions for both the Windows and Linux operating systems. (Macintosh
version will be available within a few days.) A few key new features
include ventilated slab, fully-coupled 1-D finite element heat and
moisture transport model, thermal chimney, CoolTower, additional
detailed refrigeration component models, DC-to-AC inverter and simple
battery, and direct output to SQLite. We have updated and extended
capabilities throughout the existing building envelope, daylighting, and
HVAC equipment and systems portions of the program.
EnergyPlus V 3.0 is available at no cost from the EnergyPlus web site:
www.energyplus.gov
Energy Design Plugin for Google SketchUp: The Energy Design Plugin
for the GoogleSketchUp 3D drawing program. The plugin makes it easy to
create and edit the building geometry in your EnergyPlus input files.
The plugin also allows you to launch EnergyPlus simulations and view the
results without leaving SketchUp.
EnergyPlus Example File Generator: A Web-based service is available that
creates and runs EnergyPlus input files for simple models of commercial
buildings. The input files (and annual results summary files) are sent
to your e-mail address as attachments. This is a pilot project and is
currently made available only as a BETA service. You can access the
service and customize the characteristics of the building you want to
model on the EnergyPlus Example File Generator Application
The set of example input files now includes full-blown models of typical
new construction (drawn from the DOE Commercial Benchmarks project).
What's New in Version 3.0?
Datasets
* Refrigerant properties for R404a, R410a, and R507a added to
the refrigerant database.
* New library of compressor performance curves for refrigeration
systems created.
* New performance curves for condensing and high-temperature
boilers.
* California Title 24 Time Dependent Valuation (TDV) factor
schedules (2008) dataset added.
* California Title 24 operating schedules dataset added.
Input
* Version 3.0 includes widespread changes to input syntax. The
complete set of input objects was revised to make EnergyPlus's input
'language' more consistent, logical, and informative. Although the
majority of words used to describe input object names, field names and
key choices have changed, the underlying meanings remain the same. (Yes,
this will require substantial changes to input data files--aided by the
Transition program which can be accessed through the EP-Launch utility.)
* New examples input files for all new features.
Zone Model
* New Ventilated Slab model includes radiant heating and cooling
interactions with hollow core slabs
* Infiltration models now allow air flow rate per unit of
exterior wall area as an optional input.
* Pipe heat transfer loads added into zone air heat balance
calculations.
* New optional algorithms for fully-coupled, 1-D finite element
heat and moisture transport model for simulating the movement and
storage of heat & moisture in and through building surfaces.
* Moisture transfer function and moisture finite difference
models removed.
* The algorithm for variable system timestep was revised.
Changes include uniform system timestep length across zone timestep and
stricter management of history terms for zone air conditions.
Natural and Mechanical Ventilation
* Additional hybrid (mixed-mode) ventilation controls added to
allow global control of surface openings based on master zone, limit
opening levels based on wind speed, and allow control of Mixing and
Ventilation objects.
* Temperature limit controls added to Mixing and Cross-Mixing
objects.
* New Thermal Chimney model added--uses solar radiation to
enhance natural ventilation.
* New CoolTower model added--uses natural evaporative cooling to
cool incoming air.
* Added new outside air minimum and maximum fractions to easily
model 100% (or any fixed value) OA systems, leakage or stuck OA dampers.
HVAC
* Refrigeration system capabilities expanded with more detailed
component models. Users can now simulate: (1) variable evaporating
temperatures, (2) variable condensing temperatures, (3) mechanical
subcoolers that transfer refrigeration loads from less efficient low-
temperature systems to more efficient medium-temperature systems, and
(4) liquid suction subcoolers.
* Improved error trapping for refrigerant and glycol properties
at extreme temperatures and pressures.
* Single-speed cooling towers can now use fluid bypass as
capacity control, saving water but requiring more fan energy.
* New linear curve to complement other curve objects.
* Absorption chiller now can connect to steam or hot water loop.
* Enhanced absorption chiller model added.
* Radiant-convective baseboard model added.
* Boiler model upgraded to include performance curve which
accounts for load as function of operating temperatures.
* Set Point Managers now test for control node conflicts.
* New system availability managers added: Scheduled On, and
Scheduled Off.
* New Underground Pipe object added; upgraded Pipe Heat Transfer
objects.
* New Fluid Cooler objects added--single and two-speed dry
cooling towers for hydronic loops.
* Component sizing factors added for boilers, chillers, and
cooling towers.
* Added chilled water thermal storage tank models for both mixed
and stratified tanks.
On-Site Energy Supply
* PV model restructured to separately model inverters and
storage systems.
* DC-to-AC inverter model added along with simple battery model.
* Simple Photovoltaic-Thermal model added for pre-heating
outside air and hot water heating.
Economics
* Energy cost calculations now includes real time pricing,
minimum monthly charge, and buy/sell/net metering as new inputs
* A new monetary unit object (Currency Type) added
* Additional economic reporting of energy and demand for each
charge
Output
* SQLite added as another output format option, providing
optional export of time-series results directly to database.
Utilities
* EP-Launch now handles blank weather files as if no weather
file is specified in group simulations.
* IDF Editor new features include wrapping long text strings
over multiple lines within cells, required fields now shown with blue
field names, and added recently used file list.
* WinEPDraw can be used with older (pre V3) files as well as V3
files - if placed in the proper folder.
Documentation and Guides
* Input/Output Reference and Engineering Reference updated and
extended for all new features and updates and renaming. Total
documentation now exceeds 3800 pages.
And many other enhancements and speed improvements throughout.
See http://www.energyplus.gov/features.html
features added in this and previous versions.
Suggestion: get as much memory as possible in your computer for running
EnergyPlus. A recent team upgrade from 1.8GHZ machine with 768MB memory
to a 2.1GHZ machine with 2GB memory caused one file to go from a full
annual simulation (5 zones) at about 8 minutes to a 2-1/4 minute run on
the newer machine.
Update on User Interfaces and Tools?
Many user interfaces that create and run EnergyPlus input files and
display results graphically are available (Demand Response Quick
Assessment Tool, DesignBuilder, Easy EnergyPlus, EFEN, Hevacomp, and
HLCP) and under development (ComFen, TREATPlus and EPlusInterface).
Check our web site (http://www.energyplus.gov/ep_interfaces.html
information on these and other interfaces.
Utilities and tools for creating, editing, and running input files that
come with EnergyPlus include IDF Editor, EP-Launch, and HVAC-Diagram
(see http://www.energyplus.gov/ep_utilities.html
creating, editing, and displaying EnergyPlus input files are also
available, including DrawBDL, EcoTect, EnergyPlugged, ESP-r, Green
Building Studio, EzDrawPlus, IFCtoIDF, TSe+, and EzPlus-Parm. See
http://www.energyplus.gov/third_party_tools.html
information.
EnergyPlus Training Workshops
We will continue to offer training workshops throughout 2008 and 2009.
For more information, please see: http://www.gard.com/training.htm
What's going on in V3.0.0?
Will there be any considerable difference between version 2.2 and 3.0?
Yes.... and no. The basic structure of EnergyPlus is still as it has
been but there are some significant changes that you will want to be
aware of.
As always, there are a number of new features and bug fixes. The
highlights of features for this version are listed below-see
www.energyplus.gov/features.html
features added in this and previous versions.
How about IDF and IDD? Do they remain unchanged?
There has been a whole scale revamping of the IDD/IDF naming structure
and the names of most objects and key values have changed. Your best
option is to use the included Transition program if you want to use any
older version files.
Is version 3.0 backward compatible? Can I run v2.2 file in v3.0?
See previous item. There are many changes that require you to use the
transition program for V3.0. EP-Launch can check the selected file (if
there is a version object) and you can launch the Transition program
from the EP-Launch "File" menu. You can also view the ObjectStatus
installed version. This file has detailed explanations of changes to the
objects. There is also a new option for the transition program that
allows you to supply a list of files and it will convert them for you.
The transition program is described more fully in the Auxiliary Programs
addition, we can make available a zip file of all transitions programs
and batch files such that files can be taken from much earlier versions
to current version.
EnergyPlus Weather Data
Weather data for more than 2000 locations worldwide are available on the
EnergyPlus web site: http://www.energyplus.gov/cfm/weather_data.cfm
weather data set for New Zealand. New data for China and Australia
should be available soon.)
If you know of other weather data for your country that you'd be willing
to share with the EnergyPlus user community, please contact Dru Crawley
(Drury.Crawley at ee.doe.gov
EnergyPlus Helpdesk
A helpdesk system has been set up for managing EnergyPlus user support
requests. The helpdesk system includes a download area, a knowledge base
and troubleshooting area. To submit new support requests (tickets) or
search the knowledge base, please go to energyplus.helpserve.com
files and reply to tickets via e-mail at EnergyPlus-Support at gard.com
the helpdesk since early May 2008. This is the best way to get your
specific EnergyPlus questions answered.
EnergyPlus_Support Group at YahooGroups
Are you a commercial or academic user of EnergyPlus? Join more than
1800 EnergyPlus users in the user-to-user email group on YahooGroups-a
place to ask questions and share information with other EnergyPlus
users. The YahooGroup also provides a searchable archive of all 7+ years
of discussion. You can also upload files to share with other users.
While the EnergyPlus development team does monitor the YahooGroup list,
the best place for individualized support is the EnergyPlus Helpdesk
The main web page for the group is:
http://groups.yahoo.com/group/EnergyPlus_Support
To subscribe, send an email message to:
EnergyPlus_Support-subscribe at yahoogroups.com
If you hate to constantly receive email, you can edit your YahooGroup
membership to only send a daily digest of messages.
Building Energy Simulation User News
Want to keep up to date on EnergyPlus and other building simulation
tools? Subscribe to the bi-monthly electronic newsletter for users of
EnergyPlus, DOE-2, BLAST, GenOpt, SPARK, and Energy-10. See
http://simulationresearch.lbl.gov/un.html
BLDG-SIM
Join the free e-mail list for users of all building energy simulation
programs. Ask other knowledgeable simulation program users your
questions--about EnergyPlus and other simulation programs. See
http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org
for information on joining this email list.
Thanks!
The EnergyPlus Team
