Re: [EnergyPlus_Support] Re: solar collector to sky radiator

On Mon, Dec 1, 2008 at 10:28 AM, Jeff Haberl <jeffhaberl@xxxxxxxxxxxxxx> wrote:

FYI:

You might also find the following PhD Dissertation useful "An Investigation of Methods for Reducing
the Use of Non-Renewable Energy Resources for Housing in Thailand", Sakkara, Rasisuttha, Energy
Systems Lab Report No. ESL-TH-05-05-01, (May).

In it are measurements made in College Station of a triple-effect solar collector used to collect electricity,
solar thermal heating and for rejecting heat a night. The conclusions are that it would be better to use
special-purpose collectors for each, as the glass in the PV panel is a poor conductor, and acts like an unglazed collector.

Jeff

8=! 8=) :=) 8=) ;=) 8=) 8=( 8=) :=') 8=) 8=) 8=?
Jeff S. Haberl, Ph.D., P.E.............................jhaberl@xxxxxxxxxxxx
Professor......................................................Office Ph: 979-845-6507
Department of Architecture.......................Lab Ph: 979-845-6065
Energy Systems Laboratory.......................FAX: 979-862-2457
Texas A&M University..............................77843-3581
College Station, Texas, USA.......................URL: www-esl.tamu.edu
8=/ 8=) :=) 8=) ;=) 8=) 8=() 8=) 8=? 8=) 8=) 8=)

________________________________

From: EnergyPlus_Support@xxxxxxxxxxxxxxx on behalf of ian8512
Sent: Sun 11/30/2008 5:56 AM
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
Subject: [EnergyPlus_Support] Re: solar collector to sky radiator

Dr Li,
Cause I am handling with another project right now. I may upload the
error file a few days later. Cos I will stuggle with it afterward.

Ian

--- In EnergyPlus_Support@xxxxxxxxxxxxxxx <mailto:EnergyPlus_Support%40yahoogroups.com> , Yuen Liu <yli006@...>
wrote:
>
>
> Hi, Ian
>
> If you have already run the simulatin as is, you may have noticed
that the capacity of the panels is about 6 kW for heating. The night
time heat loss was a small fraction of this number. I may be wrong
in reading the result. as I have just installed the Version 3.0,
and some of the variables have different names.
>
> If you are still interested in knowing what is wrong with your IDF
file, I suggest that you up-load the IDF file to this group. Some
one may have a look at it.
>
> I have students working on solar panels at the University of
Malaya, Kuala Lumpur, years ago (1960's). The panel temperature was
not very low at night. The panel temperature follows the outdoor
temperature and lower by about 3 to 5 °C. The day time panel
temperature can reach about 80°C.
>
> Regards,
> Dr. Li.
>
>
> To: EnergyPlus_Support@...: ian8512@...: Fri, 28 Nov 2008 19:39:57
+0000Subject: [EnergyPlus_Support] Re: solar collector to sky radiator
>
>
>
> Dr. Li, Thanks you for helpful advice on the simulation of sky
radiator!As i am trying to investigate the feasibilty of using sky
radiator, therefore, the idea of flat plated being buried underground
doesn't work for me. But anyway, thanks for your reply, it has
inspriated me.Best RegardsIan--- In
EnergyPlus_Support@xxxxxxxxxxxxxxx <mailto:EnergyPlus_Support%40yahoogroups.com> , Yuen Liu <yli006@> wrote:>> > In
a situalation you described, I usually change the equipment
availability schedule and leave all the equipment as is.> > For
example, if you set the 'heater on' temperature below the night
temperature, it will not come on. I assume that the water usage can
also be shut off during the day.> Do the changes one at a time and
study the result.> > You also need to make sure that the DesignDay
temperature will give you the cold period between 9 am and 6 am.> > I
have not looked at the actual example file, you may have problem
turning off the circulation between the plate and the tank during the
day. However, this problem will still be there, even if you remove
the heater completely.> > Your condition seems to be that when the
outdoor temperature is higher then the 16°C the circulation is cut
off. The original condition is for the sun to heat the panel to above
a certian temperature and then circulate. This is the part I think is
causing the problem.> > If you are thinking of using this system to
collect free cold water, it may work using the ground temperature
which does not change very much, and can be left connected the whole
day, with the flat panel buried below ground.> > Regards,> Dr. Li> >
> > To: EnergyPlus_Support@: ian8512@: Fri, 28 Nov 2008 10:55:34
+0000Subject: [EnergyPlus_Support] solar collector to sky radiator> >
> > I am going to stimulate a sky radiator using an existing example
in energy plus - solar collector.In the solar collector, there are 4
components, they are the flat plate, storage tank, heater and water
use connections objects.I am trying to change it to 2 components,
falte plate and a storage tank. And the operation time will be at
night(21:00 to 6:00)and the set point temperature of the storage tank
will be around 20 deg. celeus to 16 deg. celeus.However, everytime,
there are so many errors after I attempted to change those parameter
and setting.Could somebody lend a helping hand?? > > > > > >
__________________________________________________________>
>
>
>
>
>
> __________________________________________________________
>