Virgin islands questions.

[Kachael]

Hello from a long time reader of these forums, I'm planning to move the USVI in a few months to break ground on a retirement home.

After several visits spanning several years to plan the construction and reading these forums I have a couple of questions.

Previously there was a cap on new grid tie installations, I understand that new connections are being allowed again since 2016.

Electricity is expensive running about .32 to .34 KWH from the VI power company WAPA. Second a lot of home do have solar installations, but almost all are grid tied. WAPA is not the most reliable power supplier on a good day either, normal wind or rain storms will interrupt the power on the island. Current sun hours run about 5.5 to 6 hours per day.

Some island solar installations have generators with grid disconnects, several friends with solar have been on generators since Maria hit the islands in September 2017 until just a few weeks ago.

Currently this is what I have come up with so far, daily home power usage would consist of two refrigerators, cistern pump and pool pump as the major loads. smaller loads would be the LED TV's and lighting.
Additional loads would be four 5000 to 10000 BTU a/c split units.

Plan the electrical service during the construction to allow the installation of solar grid tie, battery back up and generator back up? rather then adding later as needed?
Size the battery and generator to the electrical loads less the a/c split units, taking those off line when the power is interrupted

Hook up to the grid and watch the actual usage over several months and size the PV system at that time?
Current roof design allows for 20 standard panels minimum.

Would prefer a bullet proof system that is easy to service and upgrade the electronics. Panels would need to be wind and storm rated for HVHZ. 150 MPH

Would a "Power wall" type battery installation be a better choice for energy storage if the grid is down for several days to weeks rather than running the generator all the time?

Just thinking of the cost per run hour "Power wall" vs generator.



Thanks for any thoughts,

Chris

[Guest]

I truly grateful for this post. I

[Mike90250]

I truly grateful for this post. I

me too,, we are watching you

[Mike90250]

....
Hook up to the grid and watch the actual usage over several months and size the PV system at that time?
Current roof design allows for 20 standard panels minimum.

Would prefer a bullet proof system that is easy to service and upgrade the electronics. Panels would need to be wind and storm rated for HVHZ. 150 MPH

Not sure about 150mph rated gear, usually at 150mph, the flying debris will strip your panels from the mounts. (lawn chairs, BBQ's, small trees, cows)

Me, this would be my plan. You are going to need a generator, if PV is damaged or bad weather persists. Buy it and wire it properly with a emergency circuits transfer switch (fridge, pump, ceiling fans, TV, microwave) All the other optional household gear, gets to wait, fuel costs more than killowatts. The more circuits you deem emergency, the larger the generator must be.
Generator can be manual or autostart, how involved do you foresee yourself ?
At construction, rough in provisions for solar and inverter. House your generator in a separate shed from the inverter & batteries, a bit of redundancy in case of fire.
Do you desire roof mount, pole mount or ground mount for the solar array ?
See if after a year, you want solar, and if you want to add batteries to the system or if the generator is going to do it?

Would a "Power wall" type battery installation be a better choice for energy storage if the grid is down for several days to weeks rather than running the generator all the time?

1 power wall will not last a typical american household 1 night, you may need a couple.

[tecnico]

sorry to ask but im new to the forum and want to know how can i make a new post ? :/ been looking around and wrote to te adm but havent still found how to post , could you please help ?

[SunEagle]

sorry to ask but im new to the forum and want to know how can i make a new post ? :/ been looking around and wrote to te adm but havent still found how to post , could you please help ?

It looks like you have been approved by the Admin to make your own posts. Go to the Forum list. Select a topic and you should see a blue button at the top left side that says "New Topic". Click on that and you should be able to create a new Thread with your first post.

[Kachael]

Hello, to Mike90250
We are currently set to visit with the architect in 2 weeks to hopefully finalize the paperwork and go over the final drafts of the plans. Because the house is set on a slope I was planning to add a outside storage room for the generator and the related equipment when the house is sited. Hopefully I can do this room for a small added cost as we do not have any additional storage in the house.

Kachael

[Amy@altE]

What type of roof do you have? That would help determine if racking can be installed for 150MPH. You can play around with IronRidge's Design Assistant, it will tell you if it can do it. You may want to look at SolarEdge's StorEdge with an LG Chem battery. You can set it for self-consumption so you store your extra energy to use yourself at night rather than selling it back. It will also provide you with some battery backup when the grid goes out, but as you said, not for the AC.