Mexstan

I am getting involved in a big new project that at this stage looks like it will be totally green. In other words, off the electrical grid as much as possible. Can anybody give me some sort of guide or links to find out:

- What power reserve (wattage) do we figure in for each house for therapy devices for old folk. This may or may not be required, but we have to factor it in even if we do not know what devices may be used in the future. I was thinking maybe three 15 amp plugs per room? Don't think we need any 220 volt outlets.

- I can easily figure out the total (max) electrical load for each house with everything on, but how do I figure out average load which of course will vary for day or night use? In other words, what figure (watts or amps) do I use to calculate the total power requirements for each house if we are sizing a solar unit? What about surge watts?

old dog

STAN> there is a good article in mother earth news on this >
you can pick up the link from something T-RAD posted on break room thread yesterday !
not trying to hyjack the thread > on your statement on safty in mexico > i can see your point > there are lots of places in AMERICA THAT I WOULD NOT WANT TO VISIT OR LIVE AS IT WOULD BE A SAFTY ISSUE AS FAR AS I AM CONSERNED >
The snow - well it is a pain however we do depend on cold weather & snow for winter sports as a large part of our winter economy up here !
I have to admit that when you have the proper veicle -propery outfitted for the weather it is fun to go out and drive through large amounts of snow >
thats why i have two grand cherokees now - one for the wife to drive (and not get stuck ) and one for me to drive - i can `basicly ignore the weather when i choose to -or go out and have fun in the snow with it if i choose to >
guess its all in your prospective _ lots of snow can make a beautiful lanscape !
claude

Clane

Google >> Leadership in Energy and Environmental Design (LEED), or Green Bulding Certification Institute (GBCI)

Should be able to point you in the right direction.

Fronty Owner

man, you got a lot of questions to answer.
look at the devices to be used to find out what their power requirements are, multiply that by the number of hours you expect to be without power and that will give you the number of kW-hr of backup you need.
Each house will probably run a good solid 25 amps (window AC) to 50 amps (central air) on average. This will also vary depending on the size of the houses and stuff like cooking appliances.
3 outlets per circuit/room is probably ok guess, figure two circuits for lights, two more for kitchen. Dont forget to GFCI all wet room and outdoor circuits.
Now for your backup. Dont rule out 220 volt. you can use a 220Volt backup to service emergency lighting and the therapy devices.

Mexstan

Thanks guys for your answers.
We don't really need A/C, but are considering some form of heating such as a radiant floor for the old folks. The new absorbtion heat pumps look interesting.

Fronty Owner

no a/c in central MX?

Mexstan

For most of the year no A/C or heating is required. Perhaps for a few days a year some form of heat would be nice, but a sweater works too. Seldom do we have heat or cold more then 5 days in a row that requires A/C or a heater. Old folks however feel cold long before the average person, so that is why we are looking at some form of heat. Our average annual temps are generally between 60 and 72 degrees F. Only a few days a year goes above or below that.

chaikwa

Why is that? You're at about the same latitude as Florida and they're hot and humid most of the time.

chaikwa.

Mexstan

'Cuz we are in the mountains with relatively low humidity the year round. Right now as I type this at 7:30 in the morning and after it rained last night, the humidity is only 60% which is high for us. It will drop a lot in the next few hours. Look at a map of Mexico and choose a spot midway north and south and midway east and west and you will be close to where I am. Oh, did I mention that I live in Paradise?

chaikwa

That makes sense.

Thanks Stan!

chaikwa.

Mexstan

More sense than some members here ....

Totallyrad

Stan, with the light heat load you might be able to use a hot water unit. There is already technology out there for heat storage for overnight use. Also, if propane or natural gas is available, longer term heating would only require running recirculating pumps to keep the water moving through a gas fired water heater.

Mexstan

Exactly. We are looking at this option too, especially if we use radiating floors. There are going to be about 500 houses in this complex, so we are looking at options such as one large "generating" station or three or four smaller stations. It is spread over about 74 acres in four "zones". Propane is readily available and fairly cheap. Natural gas is coming in but may not be available for where we finally build.

Water heating will be primarily by solar with a gas heater (probably in series) as a backup.

This is a very interesting project with franchise potential and we are looking for American and Canadian investors or partners.

Totallyrad

Stan, there is a solar project going on where they are using a focused array of mirrors to generate steam for power. I can't remember the exact location but I believe it in the U.S., probably west central.

Tons of info here about the different types of solar units and some on heat storage.
http://en.wikipedia.org/wiki/Solar_thermal_energy

Also, Google focused array water heating.

Mexstan

Thanks TR. That is the type of thing that we are looking at. All the roofs here are flat. We have many options, so the problem is figuring out the best one.