That time of year where my bill is going up and I re-think getting solar panels.
Any one with good experiences? My gut still tells me its a scam.
Several factors to consider.
Your latitude. Since you live in FLA you get a lot of sunshine each year so I’d think you’d be good on that front.
-Available roof space: How many KWh of generation can you put on your roof? And how much of the roof is at a good angle to gather photons from the sun ?
-Current electricity rates including tiers of usage. Cost per KWh? Time of use metering?
-Does your utility (FP&L?) still participate the in the original PURPA bill? Will your utility buy excess solar generation and at what KWh rate?
-Will your utility charge you a special fee for being on Solar? This is commonly referred to as a grid maintenance fee.
-What is your KWh usage per month?
-Will your roof support these panels? Most of the time the roof will support the weight of the panels and their mounting hardware, but most roofs will not support the wind loading of the panels, meaning the wind will create lift from the solar panels and they can pull the roof off of the house in high winds.
-Typically solar panels only produce about 60% of their rated output if they are installed in a fixed position, so let that figure into your ROI equations.
-Will the solar panel company give you a guarantee of the solar array output in full sun? If no then why not. This is the question that usually will keep the deal from happening because this is the corner stone of the ROI.
-Does your state or utility company offer either direct money incentives or tax breaks on installing a solar array on your roof?
-What will your home insurance think of installing a solar array on your roof? Will they raise your rates? Will they pay for any damage to the panels ?
-What about the guarantee on the roof of your house? Will that be affected by the installation of a solar array?
The return on investment is very important, as solar panels begin to degrade after year 10, and their output decreases when they get hot as well. During the life of the solar panels, typically 20 years, one needs to be able to put enough away from the savings to replace the panels and probably the inverter, at year 20 or sooner depending on the output of the panels as they near end of life of service, what will the cost of solar panels be in 20 years? As
@Acard7 mentions its just a simple trade off / shell game / scam and the only ones who come out ahead are the solar panel companies and the loan companies.
What is the goal of getting solar panels for the house? If it is to lower your electricity bill and in the process of saving you money you can keep putting away enough money to replace the components when they are at end of life then it is a good deal. The higher your electricity rates the faster the ROI should be, also if you put in more KWh of panels and can sell this excess generation back to the utility the faster the ROI and the greater the amount of money you are going to get from the excess generation. As I mentioned above, PURPA was the act signed by president carter that forced utilities to buy back and excess generation that private generators produced at wholesale prices.
How long do you expect to stay in your house? This is a big one. If you are going to stay there until the end of life of the equipment you are probably going to come out ahead by a slim margin. If you are going to install them as an upgrade to the house and make more money off of the sale of your house by doing so then this might work in your favor. Most people will not pay the higher price of a house in regards to comps and some of the banks will not include that upgrade in the appraisal.
If you are looking at doing a battery wall you need to consider at what depth of discharge DOD you are going to do to the batteries most of the time. The higher the DOD the less life you will get out of the LiFePo4 batteries. Typical service life of LiFePo4 batteries at a DOD of 50% is around 8000-10,000 cycles. If you think you going to use this battery wall to power your house when the power goes out, then the battery wall will have to be sized accordingly to what level of autonomy you want during a power outage, and not only the KWh of the battery wall but the size of the inverter and with increased inverter size the losses also increase as a function of percentage. Typically inverters are about 80% efficient at turning DC from the batteries to AC, and the remaining 20% is converted to heat.