I cannot say with any confidence, but I think this is some means of storing gas.
I have found a couple of references to "gasgård" in this document: http://www.dtu.dk/upload/administrationen - 101/om dtu/best/...
And here is the standard wikipedia article for ways that natural gas can be stored: http://en.wikipedia.org/wiki/Natural_gas_storage#Types
I also came across a few forum entries which intimated "meeting as the 'gamle gasgård'", which to me suggests something like "gasometer". I remember as a child, my parents would refer to the collection of gasometers in my home town as the "gas farm", but I can find no references to this being used in a professional context.
I hope my ramblings are of some help.

concurring with Richard Green on (above-ground and underground) gas storage facilities:

About DTU Energy Conversion - DTU Energikonvertering
www.ecs.dtu.dk/English/About DTU Energy Conversion.aspx‎
The key technology areas of the Department include fuel cells, electrolysis, batteries, solar cells and ***hydrogen storage***.

Why Store Natural Gas? - Floridian Natural Gas Storage Company ...
www.floridiangasstorage.com/Whystorage.html‎
***Florida's geology is unsuitable for in-ground gas storage, so the state has previously ... Above-ground storage facilities offer several advantages*** over alternative ...

Natural Gas Storage Solutions - VOLANDS™ - EnerSea
www.enersea.com/solutions/gas-storage.html‎
VOLANDS (Volume Optimized Land Storage) is EnerSea's innovative, ***above-ground compressed natural gas land-based storage technology***. Building on the ...

Gas Storage Bergermeer - Realising tomorrow's infrastructure today
www.bergermeergasstorage.com/‎
***Underground gas storage using depleted reservoirs is a proven technology with ... The Gas Storage Bergermeer facility*** will begin operations in April 2014 with ...

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Note added at 8 hrs (2013-05-13 02:29:53 GMT)
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power utilities and gas storage facilities:

Storage of Natural Gas - NaturalGas.org
www.naturalgas.org/naturalgas/storage.asp
However, ***with the recent trend towards natural gas fired electric generation***, demand for ... was part of the bundled product sold by the pipelines to distribution utilities. ... ***There are basically two uses for natural gas in storage facilities***: meeting ...

Utilities make first draw from gas storage - The Alaska Journal of ...
www.alaskajournal.com › ... › December-Issue-1 2012
The new Cook Inlet ***Natural Gas Storage Alaska, or CINGSA, facility is ... on new electrical generation and power distribution projects*** they have ...

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Note added at 3 days21 hrs (2013-05-16 15:24:54 GMT)
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very appreciative of your gesture

Thanks!