Re: Measuring albedo

["LyndonZimmermann" <lyndonz@xxxxxxxxxxxx>]

Pierre,

thanks for your response. I am modelling roof mounted solar hot water
systems. I expect the reflected radiation component would come from well
away from the array, and in the direction of orientation.  A global albedo
would not be particularly representative, dominated by surfaces below and
behind the array.

Two cases I have are arrays with highly reflective buildings immediately to
the south (we are in the southern hemisphere of course, with the sun to the
north) and sitting on bright galvanised roofing.  But the reflected
radiation on the array comes not from these surfaces but sporting fields in
one case, and a dull brick building in another.

Any further clues?

Regards,

Lyndon Zimmermann

At 14:44 18/04/00 +0200, you wrote:
>>What practical methods are people using to measure or estimate albedo for
>>their modelling?
>
>If you want to easily measure an albedo, you best take a pyranometer which
>you first have facing the sky (measure of incident radiation), than the
>ground (measure of reflected radiation). The ratio gives the albedo. If you
>measure close to the ground it is a local value, if you go higher you get a
>global value.
>
>Pierre
>*************************************************
>Pierre Hollmuller
>CUEPE (Centre universitaire d'etude des problemes de l'energie)
>Universite de Geneve
>Batelle batiment A
>7 rte de Drize
>CH - 1227 Carouge
>
>tel: (+41) 22 / 705 9649
>fax: (+41) 22 / 705 9639
>e-mail: pierre.hollmuller@cuepe.unige.ch
>*************************************************
>
>
Lyndon Zimmermann and Associates (Business number 0442221W)
Sustainable Energy Consultants
24 Waverley St, Mitcham, South Australia, 5062
tel +61-8-8272 9262 mobile 0414 91 4577 fax +61-8-8172 1494
email lyndonz@senet.com.au URL http://users.senet.com.au/~lyndonz

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