A: The ideal solar roof would face due south with no obstructions to shade it, and be pitched at 25-30 degees (about 6 or 8/12 in roof lingo).
“Ideal” is just that, and most situations require compromise, but rare is the property that solar can’t be placed on. Often panel racks need to be tilted to a more optimal angle, sometimes when shading issues can’t be avoided, using a different inverter type will allow power production to be minimally impacted.
Ground mounting options vastly increase the likelihood of getting optimum solar placement to maximize power output. Unfortunately, not everybody has lots of excess property lying around.
A: A typical 8-10kW system requires approximately 750-850 square feet of roof space with a relatively unobstructed south-facing exposure.
For those without such space/orientation on the roof, and for larger systems, ground mounted systems utilize racks constructed of metal which hold the solar array racking. A typical 7kW system arranged in a horizontal row would be about 44' long and about 9’ high. Some homeowners have a privacy-type fence built around ground arrays, while others enjoy showing theirs off.
A: A loose rule-of-thumb is for every 1kw of panels, south facing and unshaded, will knock about $18/month off your light bill (on a 12 month average).
Our largest residential systems have been 25kw, and they have been producing an average of $500/month for the last several years.
A: While it varies with panel/inverter types and installation variables, we can do some systems for as low as $2/watt. To put that in perspective, in 2008 when we started Solar Louisiana, we were installing at $8/watt, and we were about the lowest in the state. We still are.
A typical example of a simple grid-tied system would pay for itself in less than 5 years (20+% return on investment). After that, it’s free power for the remaining decades of the system life.
A: All of the panels we use have a minimum 25 year power output warranty; usually that is an “80% power output at 25 years” guarantee. Most inverters come with a minimum 10 year warranty, and some companies offer an extended warranty option. With no moving parts, a typical system will continue to quietly and efficiently put out power for several decades.
A: “Grid tied” means your system is connected with your current utility grid at your meter by use of a “net meter” installed by the utility company, with no batteries installed to store the excess power you produce. The utility grid becomes your energy storage.
A: Net-metering simply means that your utility meter flows in both directions. When you are producing energy from your system in excess of your current usage, your meter rolls backward, sending the utility company your surplus power. At night or when your air-conditioner is really working overtime, you seamlessly draw power back from the utility company to meet your energy needs. Some utility companies in La. cancel out your produced kW hours with the ones you consume from them on a one-for-one basis. Most of the larger ones (Entergy, CLECO etc.) only credit you with "avoided cost", in other words, you send it to them at the wholesale rate (=/-.045/kwh) and buy it back at retail (+/-.09). They're crooks.
A: Not with a strictly grid-tied system. It has automatic disconnects built in for safety to eliminate the danger to utility workers of possibly being electrocuted by power generated by your system.
Systems designed with a back-up of batteries can operate safely and automatically switch on when the grid goes down, allowing (depending on size & design) either the entire home or just critical systems such as freezers, fridges etc. to continue to operate.