Green Energy

+1. And not just the high cost, but also the reliability (or unreliability) of the grid. I was reading that some panels have now reached 400 watts. Seems like lithium batteries are cheaper than ever too. I'd love to hear about any recent installs.

I don’t know about the latest developments in battery technology/costs.  However, we have a solar engineer in the family and he designed a solar system for us in PR last year. 

He estimated my cost for an off grid system using the best components, panels & battery  available at that time (no labor cost included  since he would do the installation) at about 30 - 35K.  No costs included for future maintenance of the system.

My average electric bill here is about $80 a month.  At that rate, it would take over 30 years to break even. Of course, the electric rates are sure to rise over time, so the payback may be shorter.  I don’t think it is cost effective to , in effect, pre pay our electric costs for thirty years. 

That being said, the benefits of being off grid are very appealing to me, so I may do it anyway. It’s just a very big upfront cost.

Anyone with experience in off grid solar systems, please give us your feedback.

Sitka, the main concept about Solar power is that it is your system and that it is reliable. Therefore you are eliminating the uncertainty of the current grid. You top that with the ability of powering your own water pump in combination with a Cistern and a rain recovery system and your dependance on others goes way down. Even if today it cost more than the current rates, those rates are going up and up almost every year and the cost of new propane based generation and construction of the system will be passed on to the consumer. Long run your own private solar system makes a lot of sense.

I am interested in the latest update on lithium battery costs as they are a big part of the cost.

Alternative battery systems are possible, a friend of mine built his solar system using lead/acid batteries and claims it works fine.  They do take a larger storage area and have a limited life.

Some states provide for selling excess power back to the grid.  I don’t think PR allows for that.

Sitka wrote:

I am interested in the latest update on lithium battery costs as they are a big part of the cost.

Alternative battery systems are possible, a friend of mine built his solar system using lead/acid batteries and claims it works fine.  They do take a larger storage area and have a limited life.

Some states provide for selling excess power back to the grid.  I don’t think PR allows for that.

Selling electricity is known as "net metering" and Puerto Rico does allow that.  In short, your solar array is connected to the grid (it's an on-grid system) and when the sun shines and you produce more power than you consume, your meter runs backwards.  At night, it runs forward.  The utility usually pays wholesale prices for electricity, so you won't get rich if you overproduce, so your array should match your needs.  And with a pure on-grid system, when the grid goes down, so too does your solar generation.  This is the least expensive type of system, but only makes sense where the grid is reliable.  You could put such a system together and then buy a generator for emergency use.

The system you seem to be considering is on-grid with battery backup.  This is a bit less efficient and significantly more expensive than on-grid, but solves the problem of an unreliable grid.  Regarding batteries, banks of lead-acid are pretty common for on-grid with battery backup, but they produce toxic gases, so must be in a ventilated space outside of the living space.  They have the advantages of being relatively cheap and readily available.  There are other considerations when selecting batteries for your battery bank, including depth of discharge and the number of cycles it can handle.

Oh, I meant to add that your quote for a system struck me as high, but I have no idea what your monthly electric use is, and you did say that the quote was for the best components available.  Cost of a solar power system will depend on a host of factors including the amount of power (in KWH) produced, whether it is on-grid, on-grid with backup, or off-grid, and the type and number of batteries you need if it is one of the latter.  I've seen complete "kits" capable of producing 4.5 KWH for about $9000 if memory serves.

OK, one more edit.  A quick article on the average cost of a 4.5KWH solar array can be found  here.

PR could do much more to encourage solar energy for household use.  As far as I know, we have no financial or tax incentives from the government here. Considering the recent experience with Maria, I don’t understand why we don’t have strong support for solar systems on the island.

Sitka wrote:

I am interested in the latest update on lithium battery costs as they are a big part of the cost.

Alternative battery systems are possible, a friend of mine built his solar system using lead/acid batteries and claims it works fine.  They do take a larger storage area and have a limited life.

Some states provide for selling excess power back to the grid.  I don’t think PR allows for that.

Seems lead acid batteries are very popular in PR, most of the installations I seen use them.

PR does buy electricity from People, but that means you need a connection to AEE and they charge you a monthly fee for that, they rotate your electric counter backward to give you credit but the credit is minimal. They also have to come and inspect your installation, and change your meter, these two takes months to occur, mean time you cannot be connected to AEE and to the solar panels, it is one or the other until certified. I heard of people waiting 6 months.

WarnerW, great info! Do you have a solar system in PR, or have you just done your homework?

Homework, I'm afraid.  Still on the mainland, looks like 4 more years until retirement.  Been trying to find undeveloped property in the right location for the right price.  I can afford to be patient, which is a necessary virtue when trying to get things done on the island.  As an example, I've got an offer on a bank-repo'd property.  My offer has been on the table for two and a half years now, as the courts work to clear the title.

Yes, thanks, Warner for a great post. I see I have a lot of homework to do, as well.