Although this has been the standard procedure for defining the
heating design day, I question the underlying logic and think
that will lead to oversizing. If the building is unoccupied,
i.e., no occupants, no lights, no equipment, then why would it be
heated to standard operating levels? I understand combining all
the worst case conditions to get a design load, but not when those
worst case conditions tend to exclude some others from ever
occurring.
Joe
Joe Huang White Box Technologies, Inc. 346 Rheem Blvd., Suite 205A Moraga CA 94556 yjhuang@xxxxxxxxxxxxxxxxxxxxxxxx http://weather.whiteboxtechnologies.com for simulation-ready weather data (o) (925)388-0265 (c) (510)928-2683 "building energy simulations at your fingertips"
Whatever you specify as applicable on a Winter DesignDay is included.. Most designers calculate heating loads, however, with zero lights (or maybe 5% for security lights), zero equipment and zero people.
Most of the time, this makes sense, e.g., a long holiday such as Christmas or New Year, when everyone is gone and the building is quiet and dark. the Schedules might look something like:
SCHEDULE:COMPACT
Sched_PeopleAssembly Fraction
Through: 12/31
For: Weekdays Until: 8:00,0.00 Until: 11:00,0.20 Until: 18:00,0.80 Until: 22:00,0.20 Until: 23:00,0.10 Until: 24:00,0.00 For: Saturday Until: 8:00,0.00 Until: 11:00,0.20 Until: 21:00,0.60 Until: 22:00,0.80 Until: 23:00,0.10 Until: 24:00,0.00 For: Sunday Holidays Until: 8:00,0.00 Until: 13:00,0.10 Until: 22:00,0.70 Until: 23:00,0.20 Until: 24:00,0.00 For: SummerDesignDay Until: 8:00,0.00 Until: 11:00,0.20 Until: 18:00,0.80 Until: 21:00,0.70 Until: 22:00,0.80 Until: 23:00,0.20 Until: 24:00,0.00 For: WinterDesignDay AllOtherDays Until: 24:00,0.00
SCHEDULE:COMPACT
Sched_LtgAssembly Fraction
Through: 12/31
For: Weekdays Until: 6:00,0.05 Until: 9:00,0.40 Until: 22:00,0.75 Until: 23:00,0.25 Until: 24:00,0.05 For: Saturday Until: 7:00,0.05 Until: 9:00,0.30 Until: 23:00,0.50 Until: 24:00,0.05 For: Sunday Holidays Until: 7:00,0.05 Until: 12:00,0.30 Until: 22:00,0.65 Until: 24:00,0.05 For: SummerDesignDay Until: 6:00,0.05 Until: 9:00,0.40 Until: 22:00,0.75 Until: 23:00,0.50 Until: 24:00,0.05 For: WinterDesignDay AllOtherDays Until: 24:00,0.00
SCHEDULE:COMPACT
Sched_PlugsAssembly Fraction
Through: 12/31
For: Weekdays Until: 6:00,0.05 Until: 9:00,0.40 Until: 22:00,0.75 Until: 23:00,0.25 Until: 24:00,0.05 For: Saturday Until: 7:00,0.05 Until: 9:00,0.30 Until: 23:00,0.50 Until: 24:00,0.05 For: Sunday Holidays Until: 7:00,0.05 Until: 12:00,0.30 Until: 22:00,0.65 Until: 24:00,0.05 For: SummerDesignDay Until: 6:00,0.05 Until: 9:00,0.40 Until: 22:00,0.75 Until: 23:00,0.50 Until: 24:00,0.05 For: WinterDesignDay AllOtherDays Until: 24:00,0.00
On Tue, Jul 31, 2018 at 2:07 PM, my_sunny_night@xxxxxxxxx [EnergyPlus_Support] <EnergyPlus_Support@xxxxxxxxxxxxxxx> wrote:
Hello All,
Is the internal heat gain from occupants taken into account for heating equipment sizing?
Thanks
--
James V Dirkes II, CEO / President
The Building Performance Team Inc.
1631 Acacia Dr, Grand Rapids, MI 49504
(alphabet soup of efforts for greater understanding: PE, BEMP, BCxP, LEED AP)
Direct / Mobile: 616.450.8653
jim@xxxxxxxxxxxxxxxxxxxxxxxxxxx
Website l LinkedIn
Coffee conversation:
A friend describes himself as “mediocre”. In my estimation, he’s clearly amazing and exceptional, so it irritates me to hear him say that. Upon some reflection, I realize that he may be right.
Only one person in the world is the (literal) world’s best. All of us can improve and should be actively improving. That means we’re all in the middle � aa mediocrity of sorts. Maintaining a sense of our need to become better and appreciation of others’ greater talents is also a way to maintain healthy humility. I think I’m up for mediocrity � in a wonder-filled,, amazing sort of way.
__._,_.___
Posted by: Joe Huang <yjhuang@xxxxxxxxxxxxxxxxxxxxxxxx>
EnergyPlus support is found at:
http://energyplus.helpserve.com or send a message to energyplus-support@xxxxxxxx
The EnergyPlus web site is found at:
http://www.energyplus.net/
The group web site is:
http://groups.yahoo.com/group/EnergyPlus_Support/
Attachments are currently allowed but be mindful that not everyone has a high speed connection. Limit attachments to small files.
EnergyPlus Documentation is searchable. Open EPlusMainMenu.pdf under the Documentation link and press the "search" button.
__,_._,___