school me on my solar potential

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logjammed

Member
Jul 24, 2008
65
western ma
normally I browse the boiler room and wood shed,but this electrical increase is concerning. my situation I think is pretty good for solar. I have 9 acres with a business(repair shop) and a two family on the property. I would like to find out the best options for me. I am 45 yrs old and I believe purchase is the best option for me for return on investment,but could be wrong. Also should I oversize??? I will re-post with my electrical consumpsion when I receive my next bill. Also will be calling some install companies to see what they say,but I can't question what I am told. any help appreciated . more info. I would like cover all electric costs. there are 3 meters on the property. one meter for the garage,one first floor, and one second floor. the garage is a legal business and would be paying for solar. apartment electric would be inc. in rent w/increase.I have called a local pv installer for a consult. Do you tie into one meter??? What is a realistic distance to meter??? I still will update with total annual kw for all meters.
 
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I think figuring out what you want to do is your first step. Do you want to go off grid? Do you want to be grid tied? If grid tied, do you want to make 100% of your power or some portion of it?

A call to your utility might be a good idea to learn what fees and rebates you could expect.

Last I'd look at how much power you use and figure out ways to consume less. This will make a smaller, less expensive system do more for you.
 
PVwatts is a good place to start. http://pvwatts.nrel.gov/
I'd suggest figuring out what size system you'd need for 100% coverage and go from there.
In some states, oversizing your system can end up costing you more in fees. You need to check whether you state allows net metering and what utilities pay for excess production. In some cases, they pay much less than the going rate so oversizing doesn't pay.
 
Depending on your tax situation, you want to figure in the 10% investment tax credit that runs out in 2016. Most of the mass utilities are very generous with solar systems but you do need to check what incentives apply. This website will give you a good start.http://programs.dsireusa.org/system/program?state=MA . At some point you run into interconnect requirements and that is usually the point that you want to avoid.
 
I have 9 acres....
I am aware of about 8 PV installations near me. Apart from sizing and the questions already addressed, siting is very important. Ideally you want a site with no shading, and quite distant trees can still provide quite a bit of morning and afternoon shading. If snow is a consideration, you would want to consider ground mounts so that snow may easily be brushed off the panels. Roof mounts often make snow removal difficult to impossible. Then you want to determine DC panels with a string inverter or each individual panel having a micro-inverter. Where you have shading moving across various panels during the day, that shading can reduce production materially with string inverters; impact may be reduced substantially with micro-inverters.

You can follow my experience 6.5kw System

I am adding 5.4kw, another 20 panels, to my system this Spring.
 
Look at your annual electrical consumption, not just any given month. Ideally, look over a collection of years, if you have access to that much data. When you start playing with PV Watts, you want to have an idea how much energy your property consumes over the entire year.

As Limestone noted, finding ways to conserve electrons are usually cheaper than collecting them from sunshine. I'm lucky, I've shaved off ~20% of my consumption to get down to ~10MWh/yr, then I collect 6MWh/yr, and buy ~4MWh/yr.
 
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The driver for solar is very incentive specific. Many of the Mass utilities and localities have very good short term and long term incentives that turn solar into a very short term payback. A former coworker covered his roof with panels generating far more power than he needed as he was going to get long term incentives for every KW generated. The system would pay off in less than 4 years and after that would return around 8%. In Mass, ratepayers have a choice, they can either pay to install solar on their property or pay surcharges on their bills to have the neighbors install it. The electric surcharges are going to be going up rapidly. The model is probably unsustainable but many folks are grabbing it while they can.
 
normally I browse the boiler room and wood shed,but this electrical increase is concerning. my situation I think is pretty good for solar. I have 9 acres with a business(repair shop) and a two family on the property. I would like to find out the best options for me. I am 45 yrs old and I believe purchase is the best option for me for return on investment,but could be wrong. Also should I oversize??? I will re-post with my electrical consumpsion when I receive my next bill. Also will be calling some install companies to see what they say,but I can't question what I am told. any help appreciated .
I had an 8.65 system installed on my roof last summer. I wish I oversized the system for future needs(electric car). A neighbor installed a ground mount system that tracks the sun. I hear its more expensive but less panels. Not sure if you have the room, I didn't. The snow we had in Jan covered most of my panels until it melted in March. I live in southern NH.
 
Tracking rack mounts are a lot more expensive than standard fixed solar panels. VT has incentives in place that were written to encourage trackers so there are lot installed. They give more power in the winter. For grid tied systems, they rarely make sense economically but those off grid that need to optimize winter production sometimes use them. They also are set up to park vertically so snow is far less prone to stick to them.
 
A rule of thumb on 2-axis tracking is about a 30% gain in production over fixed racking. While that's attractive, it may be less costly to achieve the same result with fixed racking and additional panels, if you have the space. Plus, tracking involves mechanical components which may require additional maintenance and may not be reliable in cold, snowy and icy environments.
 
I am not advocating trackers but these http://www.allearthrenewables.com/ seem to hold up to the weather in VT which is about as cold, snowy and icy as most would expect. The passive trackers that use refrigerant transfer between tanks are not sold nor suitable for cold, snow or icy environments although I know of a few used by seasonal camp owners.
 
Depending on your tax situation, you want to figure in the 10% investment tax credit that runs out in 2016. Most of the mass utilities are very generous with solar systems but you do need to check what incentives apply. This website will give you a good start.http://programs.dsireusa.org/system/program?state=MA . At some point you run into interconnect requirements and that is usually the point that you want to avoid.
Did you mean the 30% ITC that expires at the end of 2016?
 
Did you mean the 30% ITC that expires at the end of 2016?
Yup 30%you are right for solar. I had the 10% in my mind for CHP projects.
 
normally I browse the boiler room and wood shed,but this electrical increase is concerning. my situation I think is pretty good for solar. I have 9 acres with a business(repair shop) and a two family on the property. I would like to find out the best options for me. I am 45 yrs old and I believe purchase is the best option for me for return on investment,but could be wrong. Also should I oversize??? I will re-post with my electrical consumpsion when I receive my next bill. Also will be calling some install companies to see what they say,but I can't question what I am told. any help appreciated . more info. I would like cover all electric costs. there are 3 meters on the property. one meter for the garage,one first floor, and one second floor. the garage is a legal business and would be paying for solar. apartment electric would be inc. in rent w/increase.I have called a local pv installer for a consult. Do you tie into one meter??? What is a realistic distance to meter??? I still will update with total annual kw for all meters.
looks like my average annual usage for all 3 three meters (last year) was 609kwh
 
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