Generators & Solar power banks

Better options are available today.

After Maria, everyone with the solar /net metering system went nuts. They had thousands of dollars in solar panels in-tact on their roofs, but since WAPA’s transmission lines were down, they couldn’t use any of the electricity they were generating. 

I spoke to Mike Bruno at Energywise recently. Besides better performing solar panels and batteries, a better computer exist that monitors everything. As he explained, during daylight hours you use electricity directly from the solar panels and charge your batteries. At night you draw from the batteries. If we get several days of cloud cover (very rare) and batteries get depleted, the monitoring computer switches to WAPA. The switchover from one form of electricity to another takes place in a microsecond, lights barely flicker.

A diesel or gas generator would be a 4th option with this system, but most likely only used during extreme events.

Ive got a small, portable, gas 5k generator that’ll be my last resort. It got me through the 81 powerless days after Maria, but once I get this system up and running, I doubt I’ll ever start it again.

Be aware, this system isn’t cheap, but I think it’s the best option out there right now. Mikes reputation is unquestionable when it comes to design and installation.

@singlefin

Thanks, Mike replaced my panels after Marie. I agree he's a great guy.  It's a small system and after researching it most of the day, I am not sure if it can keep the batteries charged without adding more panels.  I'll be down in 3 weeks, so I will talk to Mike again, but I think he quoted me a price before and it was pretty expensive (thought he said approx 20k, but I could be wrong).  What size solar system do you have?  Mine is only 3.5 KWh, but use about 10 KWh per day (have rented out both the house and small apartment for a few months so i'm sure that would normal use for my wife and I).  Any further input would be greatly appreciated.

I’m in the middle of a large renovation/addition. I had Mike look things over so I could run whatever conduit he needs now. It’ll probably be middle of next year before I’m ready for him to do the Solar instal. I’m looking at around 20k as well for his work. Between the new pool pump and a/c units, I figure the solar system should pay for itself in about 5 years. 

I don’t believe WAPA’s rates will ever decrease and their reliability will remain iffy at best. If their fees were more reasonable I would stick with them. My wife and I use very little power. I already collect and filter all my own water, privately recycle, cart my own trash, and repair/maintain the dirt road I live on.

At some point in the future, Solar panels will be the size of cell phones, batteries will store far more than they do now, and the cost of private power systems will drop substantially. If the local government doesn’t do right by WAPA soon, it'll disappear like local landline phone companies have.  

If you have solar Panels and Tesla battery bank with net metering then you do not need a generator at all. I use about 12 kw a day without running AC or about 25 when using AC. I am not very frugal as far as energy usage  

my 24 panel solar system generates between 20 and 35 kw per day. I haven’t had a WAPA bill since I installed the system. The whole system will pay for itself in about 7-8 years. It should last about 20 years and there is practically no maintenance. 

If you do get a generator, you might want to consider going with propane on the generator fuel. Diesel fuel only has a storage life of 6-12 months before it starts to degrade. Propane will last indefinitely. If you're using propane for your stove, you already have a tank for it and could add another if needed.

If you're buying a new generator, consider an inverter generator set (or converted) for propane. The inverter generators provide a much higher quality of power and most will adjust their running speed based on demand instead of running at a constant speed.

We're in the process of buying a house on STX now, and will replace the older gas generator with a Honda propane inverter generator when we get enough saved up for it (not in a big hurry). The generator provides power during the time after a hurricane to check (and repair if needed) our solar power cables before we reinstall the panels.

Propane burns quickly if you're using it for powering your home for months after a storm. I bought one with auto transfer switch for my home here in FL and have a 1000 lb. tank. Thankfully haven't had to use it for any lengthy period. Completely different being without power up here than in islands as very few places, stores, gas stations, etc., have any back up power and its hot as Hades so forget opening a window for any breeze.

On STT, my home there, has a 16K diesel generator with auto transfer switch. It runs everything on the property for main house and apt., including the AC in master bedroom. 

There are additives to maintain fuel quality.

Would love Solar but too expensive an outlay at this point in time.

Plus, if your roof goes or panels get damaged by debris during a hurricane, you're outta luck.

What do you do then?

Who do you call?

between two evils I would go with propane generator. At least it burns cleaner then diesel. But solar in VI is just a no brainer. Long term it is cheaper then alternatives and environmentally friendly. 

@Alana33

All homes and circumstances are different.

The home we are purchasing was set up by the owner/builder to allow the panels to be easily removed for safe storage in the basement before the storm comes through (and before the winds are too strong to do it safely).

IF the panels can be removed and stored safely before the storm (and IF you still have a place to mount them after the storm), there is no need to run a generator for months after a storm.

For me, not having to buy a diesel tank and store diesel and being able to use the fuel I already have onsite (propane) is an advantage.

 @daveb722

If you have a 3.5 kW solar array, you should be generating about 15 kWh per day (confirm with an expert). You may also want to ask them about whether they can install them in a way that you can easily (and safely) remove them when a storm is coming.

The house we're buying only has a 2.2 kW solar array, but the people we're buying the house from have a net metering credit with WAPA (the house doesn't have A/C, but does have plenty of breezes). Once we've been in the house for a while, we'll figure out if we need to add more panels.

The house currently has a 6 kW gas generator, but they recommended going with a 7 kW Honda inverter generator (5.5 kW on propane) when we replace it. The Honda inverter generator has a high enough quality of power (low THD) that the charger/inverter we have will also allow it to charge the batteries when the generator is running, so it doesn't need to be run around the clock. At full load on propane (5.5kW), the Honda 7000 uses 4 lbs of propane per hour.

Best of luck!

I'm too old to be climbing up on de roof and hauling stuff up and down, dealing with that in addition to all the prep work of moving outdoor furniture, plants, closing up house and connecting and putting all back on the roof.

My diesel generator has worked just fine since I purchased that house in 2003. Very little maintenance but do annual servicing in beginning of May prior to hurricane season.

Dealt with 3 months without any power on every single hurricane event 

Visited morgue to find missing friends on boats 

Heck had a 5000 kw gas generator after returning from Culebra and the devastating of  Hugo in 89.

We tied this little generator into meter so once generator was on we could have a couple lights, water, shower, flush toilets and have refrigerator on. 

Had to unplug stuff to use water and washing machine.

Forget using microwave or the dryer!

Ladies no blow drying hair if you did do that sort of thing

Ditto for Marilyn 

One really doesn't doesn't understand the anxiety, stress, mental and physical activity hurricane season provokes for many of us that have been thru way too many.

Too many Cat 5 HURRICANES in my lifetime to date.

Do whatever is best for your particular situation and budget.

Posted by: @rewired

@Alana33

All homes and circumstances are different.

The home we are purchasing was set up by the owner/builder to allow the panels to be easily removed for safe storage in the basement before the storm comes through (and before the winds are too strong to do it safely).

IF the panels can be removed and stored safely before the storm (and IF you still have a place to mount them after the storm), there is no need to run a generator for months after a storm.

For me, not having to buy a diesel tank and store diesel and being able to use the fuel I already have onsite (propane) is an advantage.

 @daveb722

If you have a 3.5 kW solar array, you should be generating about 15 kWh per day (confirm with an expert). You may also want to ask them about whether they can install them in a way that you can easily (and safely) remove them when a storm is coming.

The house we're buying only has a 2.2 kW solar array, but the people we're buying the house from have a net metering credit with WAPA (the house doesn't have A/C, but does have plenty of breezes). Once we've been in the house for a while, we'll figure out if we need to add more panels.

The house currently has a 6 kW gas generator, but they recommended going with a 7 kW Honda inverter generator (5.5 kW on propane) when we replace it. The Honda inverter generator has a high enough quality of power (low THD) that the charger/inverter we have will also allow it to charge the batteries when the generator is running, so it doesn't need to be run around the clock. At full load on propane (5.5kW), the Honda 7000 uses 4 lbs of propane per hour.

Best of luck!

 

 

LOL - You're assuming you'll have a roof after a hurricane on to which to put those stored panels. I would not count on that. 

With that said, our solar panels made it through Maria on our roof without damage.  

Propane generators are great but it can be difficult to replenish your propane supply after a hurricane. Residences go to the bottom of the pecking order for delivery - if a truck can make it to your home.

Right now we have net metered solar, a diesel generator and 3 gasoline powered generators (two that run, one for parts).

BTW - when the VI first offered net metering 6-7 years ago, the original contract allows you to sell your solar power generation to WAPA at retail dollar for retail dollar indefinitely. If the sellers have that original plan and you can keep it, you might seriously think about retaining net metering. 

@gators_mom

Laugh if you'd like, but I believe that some houses are better prepared than others to withstand Cat 5 storms.

The builder started with the Miami-Dade County building code as a baseline and then made the house stronger from there...

The roof has beams on 18 inch centers, tongue and groove wood, decking, wind and rain shield and heavier gauge galvalume screwed every 6 inches and through screwed to the beams. Every beam has a tie beam to the exterior walls and is hurricane strapped in place.  Exterior walls are block with every core poured and every other core has rebar reinforcement. Just for good measure, there are a pair of reinforced concrete bond beams between the long walls of the house to prevent them from flexing.

I'll admit I don't plan to have drinks on the porch as the next Cat 5 rolls through, but I do feel pretty good about having a roof over my head afterwards.

BTW, we checked and are supposed to be grandfathered in the net metering program. Both of these are reasons we selected this particular house to buy.

Yeah, I lost all 14 panels during maria, neighbor next to me, none.  Mike Bruno redid the install and was suprised I lost them all, he felt they weren't installed correctly.  In the NOAA satellite photos I found most of them, some as far as 4-500 feet away from the house. ☹️  Anyways, I don't think I would do propane due to the lack of getting it when the shit hits the fan as stated above or buy a 500 gallon tank.  I will have to look at costs and longevity of the unit.  Diesel would be a better option due to the fact any rescue efforts where they bring military vehicles over would require diesel to be available.  With my current solar I have always had a credit, I'm just not sure if it's powerful enough to recharge a powerwall unit.  I'm also not sure if I am allowed to add panels to the net-metering system, not sure what the requirements of the original agreement were.  When I arrive on island next month, I will meet with a few people to discuss my options.  As for my roof, it was built to the new standards and held up nicely with the exception of an object that put a 2" hole in it.  But was an easy fix.  I will not try Pro Solar as I have requested twice to be contacted on their website and had correspondence on facebook with them stating they would call.  That was 2 months ago, no call yet.  Mike has always been responsive and even offered a small generator to run my cpap machine when the power was out from Maria, fortunately the power came on 2 days before we arrived.  He's the best.

Dave

@STTsailor

I am off grid, 18 panels ground mounted, bought batteries via China, other  items like BMS, inverter etc... From alt-e in the states.  Run a propane generator as I use gas for hot water and outdoor grill.  I purposely went with much larger tank than needed 

I just singed an agreement with Mike Bauer (who seems very knowledgeable) to install 32 310 watt panels, so 9.92 kW, plus a 18.5 kW battery with 8kW hybrid inverter.  It will be installed in April just after my wife leaves for the season.  Mike is recommending the panels be installed on the roof.  I don't think my wife and I are big power users, we rarely run the AC and we are seasonal residents so the hot months were away.  We may actually set the AC at 82 0r so when were away to keep the humidity in check.  We're new to the island so don't yet have a good feel for our actual consumption.

Our goal was never to be totally off the grid but rather to be substantially free from WAPA.  We also have a 7kW generator that we can plug into the system if we are on island, WAPA's down and it's needed.  This is my first experience with solar.

A little more color on my above post as I've done a little math and research.  A 10kW solar array (ours will be 9.92) will generate between 29 and 46 kWh per day depending on location.  St. Croix I would guess is at the high end of this range.  Also, I found after a little searching the average home in Florida uses about 38 kWh of electricity a day.   Las Vegas was the highest average consumption at close to 43 kWh a day, I attribute this to the high heat in Las Vegas necessitating heavy use of AC.

Given a minimum of discipline I'm confident that my wife and I will only require minimal draw from the WAPA grid.

I looked at my WAPA usage history and there has never been a month that my house in STT, where I live full time, averaged more than 1okw a day. [Many years of history]

Same for the rental apt. downstairs - never averaged more than 10kw a day.

Same here, I looked at mine and when we had 2 people living upstairs (renters) and my 1 tenant downstairs, the consumption was 11kw per day.  with my 3.5kw system, I'm producing 12 kw per day.  So you definitely will be around 35 plus kw's and can probably not worry about ensuring every light is off, etc.  

Thanks everybody, it's interesting to get real data on usage.  Our house is about 2,600 sqft with 3 bedrooms and 3.5 baths, so not small but not huge, although we do have a good sized pool.  I'm trying to make sure every lightbulb is an LED and I've confirmed our pool pump does have the variable speed motor.  One piece of advice I got from Mike Bauer is that investment in energy conversation is generally cheaper than investment in more solar power generation.  Makes sense when I think about it.

Last year with the new mini-splits in the 1400 sqft condo I averaged 25kwh/day in July and 14kwh in November using the AC conservatively.  And every bulb but the one on the fridge is LED. And that's with taking a reading just about everyday so the average is a true average which is what counts with solar.  Hi tech monitoring, I take a pic of the meter once a day when I walk by, about the same time, and key it into a spreadsheet.

Is it fair to say the seasonal difference is a function of AC usage?  Thanks again for the data, seems like you’re meticulous in your tracking of electricity usage.  I’m now curious about our usage.  I’ve yet to receive a WAPA bill as we only moved in at the beginning of December.  I’ve setup my online account, so I can see any billing but our balance is still showing $0.00 so I’ll have to wait a little longer. 

I'm watching the usage to see how much the AC is costing and to see if there is any difference between the old and new units.

Most usage difference that would be seasonal would typically be due to AC.  Of course if you don't use AC it's moot.  You may use it in summer and not in Spring. 

WAPA billing has been messed up since Maria.  They've gotten back to billing me monthly probably all last year.  However their billing has been consistently two months behind since then.  My December bill due in January was for the October reading.  I expect the next bill will be for the November reading.  Probably why you haven't received a bill yet.

Posted by: @Scubadoo

I'm watching the usage to see how much the AC is costing and to see if there is any difference between the old and new units.

Most usage difference that would be seasonal would typically be due to AC.  Of course if you don't use AC it's moot.  You may use it in summer and not in Spring. 

WAPA billing has been messed up since Maria.  They've gotten back to billing me monthly probably all last year.  However their billing has been consistently two months behind since then.  My December bill due in January was for the October reading.  I expect the next bill will be for the November reading.  Probably why you haven't received a bill yet.

Let us know, definitely interested.  We get such a strong breeze, that AC is rarely needed, but there are those days when I could use it.  

@jaldeborgh

One conservation tip that might help is to put your pool pump on a timer. Ours only runs 2 hours per day and the water stays crystal clear. You can turn it on at the timer when you vacuum the pool, and it will save you 90% of the power your pump uses compared to running it 24X7.

We have a smaller house (1400 ft2) and don't use A/C, but our 2.2 kw solar provided a net credit with WAPA for almost 10 years for the previous owner. 

If you do see that your A/C use generates a WAPA bill going forward, you might want to run the numbers on the 'new' (read that reduced) net metering program to see if the power you would sell while off island would make it worth the cost.

When Mike Bauer looked at our home (and pool) he confirmed we had the pump brand he recommends to people and it only runs a limited number of hours.

Once we complete the system install and get a few WAPA bills we can judge where we are.  My current thinking is the next step would be to invest in conservation rather than more panels.  If we’re generating 40 kWh and using 60 kWh, we need to pinpoint the usage and make changes and/or adjust our lifestyle.  The data I’m seeing here says 40 kWh should be ample for 2 people.  My wife’s also a fairly frugal person and I’m the one guilty of buying too many toys or dragging her out to nice restaurants (she doesn’t really put up a fight).