If I have a value of 220 mega joules per guest night consumption of a
hotel room, how many kilo watts per guest night would that equel?

domrep...

1 megajoule is equivlant to 0.277777778 kilowatt hours, therefore, 220
megajoules per guestnight would be 61.11111111111 kilowatt hours.  A
kilowatt hour is one kilowatt of power being used over a period of one
hour.  So, you would be using 61 kilowatts per hour, per guest, per
night.

Thanks for your question.  If you need any additional clarification,
please let me know.

Regards,

-THV

Search Strategy:
convert kilowatt hours to kilowatt
convert megajoules to kilowatt

References:
Mark Horrell - Energy Unit Converter
http://www.markhorrell.com/tools/energy.asp

Kilowatt-hour
http://www.fact-index.com/k/ki/kilowatt_hour.html

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Request for Answer Clarification by domrep-ga on 14 Oct 2004 09:36 PDT

We already had those numbers, thanks.  What we are looking for is the
kilo watt per guest night, not kilo watt hour.

What is a "guest night" in terms of consumption?
Is a guest night 8hrs, 6hrs etc?  We know a standard exists, just
don't know what it is :)

Thanks, Robert.

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Clarification of Answer by tar_heel_v-ga on 14 Oct 2004 09:55 PDT

A kilowatt hour is kilowatt used over an hour.  Therefore, using the
numbers you provided in your question, each night, you are using 61
kilowatts per hour, per room, per guest night if you are using 220
megajoules per guest night per room.  Whatever standard for "guest
night" you are using to get the megajoule number is the same standard
you would use for the kilowatt conversion.  If you are using 8 hours
to arrive at the megajoule consumption rate, use 8 hours for the
kilowatt consumption as well.

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Request for Answer Clarification by domrep-ga on 14 Oct 2004 10:28 PDT

This is the problem!  What is a "per guest night"?  8hrs, 6hrs etc?

A standard exists for "per guest night" when you are talking about
energy consumption.
What is the standard, this is the question?

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Clarification of Answer by tar_heel_v-ga on 14 Oct 2004 13:22 PDT

domrep..

My answer is based upon your original question and is correct.  Your
clarification request is another question, entirely different from
your original question.  I would suggest you post the question "A
standard exists for "per guest night" when you are talking about
energy consumption. What is the standard?" as a separate question.

-THV

Watts (W) and kilowatts (KW) are units that describe the consumption
*rate* of energy, while KW-hrs (or Joules, or BTU's) describe the
*amount* of energy consumed.  Your request for an answer in terms of
KW/guest night (or, as you seem to want, KW/hr) therefore doesn't make
much sense.  Perhaps if you described why you want this information,
someone could help you better.

Consider an analogy in terms of water use.  KW would be equivalent to
gallons of water per minute, while KW-hr is equivalent to gallons. 
Why would you want to know gallons of water used per minute per hour?

Most comparisons of the energy efficiency of hotels are done in terms
of either energy use per square foot (i.e., KW-hr/(sq. ft.)) or per
occupant (KW-hr/person-night).  You can see how the energy useage of
your building (not limited to just hotels) at
http://poet.lbl.gov/arch/.  Comparisons are done for properties in the
same general geographical area (via zip code), so a building in Juneau
doesn't get compared to one in San Diego!

Tar_heel:

you did the calculation right, but your interpretation is wrong.  You
are correct that 220 mJ is 61 kWh.  But it is NOT true that this means
61 kilowatts per hour.  If guests use 220 mJ per night, then they use
61 kWh per night.  There are various ways they could do this; here are
a couple examples: they could use 61 kW for one hour (but not 61 kW
per hour all night--that would be more than 61 kWh), or they could use
1 kW for 61 hours (if there were 61 hours in a night).

domrep--

I have no idea what the standard is for hours per guest night.  But if
it's 8 hours, then the energy consumption rate per guest is 7.6
kilowatts.  If it's 6 hours, then the rate is 10.2 kilowatts.

Let be be somewhat inflamatory and say that when trying to understand
the energy efficiency of a hotel operation, the actual number of hours
that constitute a "guest night" is irrelevant.  The energy per guest
night figure is simply telling you how much energy it takes to support
one guest that ties up a room for an entire 24 hour period.

The way a number like 220MJ/guest-night is normally calculated is by
taking the total energy useage of a property over a given period of
time, and dividing that number by the total number of "stays" in the
hotel during that period of time (one person staying for one day = one
person-night).  The total energy used includes a "fixed" amount that
does not depend on the occupancy rate (i.e., the energy used to light
and heat common areas, light the signs and grounds, run the reception,
power the pool, etc.), and an amount that depends on the number of
guests present (washing dirty towels and sheets, hot water useage,
room lighting, HVAC energy if not a central system, vacuuming rooms
that have been occupied, etc.)

racecar..

You are completely correct in your comment.  In reviewing my answer, I
realize I mistype 61kW per hour when it should have been 61kWh per
night.  Thank you.

-THV

Besides that, beside racecars comment,

'guest night' has two meanings. 
 In UK it means night you can bring guests,
in hotel industry it has to do with occupancy
(number of guest nights per year).

My guess is that asker, when saying
"  What we are looking for is the
kilo watt per guest night, not kilo watt hour "

exhibits the usual confusion  between power and energy.

 There is an average consumption per night (occupied room)
and that, of course is measured in in kWh or Joules, not in kW.

Even if we would know 'how many hours' guest stays (awake?) the
average rate of energy consumption would be fairly meanigless number.
It can be defined, but I doubt there is a standard like that.