Solar energy used to be a thing of hippies (the environmentalists) and cowboys (the people that live really far away from civilization)—because they either really really wanted to or really really needed to. Today, it may be actually a reasonable financial decision for a household. Here we’ll dive into what it’s like to take a pair home with you, and I’ll tell you exactly how much money you can save and make off your solar panels in an upcoming post.
Solar photovoltaic panels, or solar PVs, are those quintessential dark blue shiny panels you see everywhere from large, utility-scale plants in the middle of nowhere to the tops of the thousands of solar-powered street lights. They’re the first thing we think of when we think solar power. Because of grid tie-ins, you can now sell power back to your utility in some form or another in Maryland, Virginia and DC.
Solar PV systems of multiple panels start at less than $10,000, including the inverter which you need to change the direct current energy of Nikola Tesla into the alternate current of Thomas Edison that we all use today. The national average cost of “installed capacity” was $3.48 per watt in the fourth quarter of last year, after state and national rebates, subsidies and incentives. Installed capacity is exactly what it sounds like—a turnkey installation that requires you to do nothing but sip cool lemonade as you watch money-saving technology be professionally installed onto your rooftop.
Most residential installations are between 1 and 5 kilowatts of capacity, which would cost (according to that national average) $3,480 to $17,400. However, the majority of homeowners opt for a 2 – 4 kW capacity-system.
As background, the capacity rarely (if ever) produces that much energy because the sun is rarely (if ever) perfectly directed at your solar panel. And there are a ton of other variables—you know, like clouds. But that’s the max output it’s capable of. It’s kind of like your max out bench press when you were 18 and creatine was still included in all sorts of protein supplements. You’ll never ever lift that much again in your life (nor should you), but at one point in history, under all the right (or wrong) circumstances, your machinery was capable of it.
A watt is how much energy an appliance uses at any given point, and a watt-hour is just the energy used by that appliance for one hour. A general estimate floated around the industry is that a kW of installed capacity produces around 1,300 kWh a year. That 5 kW system, then, would produce about 6,500 kWh per year.
The average home uses just over 10,000 kWh of electricity a year, which is the same as using 10,000 hours of a 1 kilowatt appliance, or 10,000,000 hours of a 1 W appliance. So a 2kW system would cover about 1/4 of the average American’s electricity needs, while a 5 kW system would get supply over half of all average use or more.
Your familiar with lights—the 100 or 60 W incandescent bulbs, 14 W compact fluorescent lights, or single-digit-watt LDC lights. Pretty much everything else draws a bit more. Fridges use upwards of 1,000 W (1 kW), things that heat up like an iron usually use more than that, and air conditioners often use around 3,500 W (or 3.5 kW)—to give you an idea. So a 5 kW solar system could handle an air conditioner with a fridge and a few other appliances on top, if it were to ever produce at full capacity and consistently.
So, while a system doesn’t really produce its “nameplate capacity” power at any given time, in contrast to coal-fired power plants, you can actually have solar panels on your house! Try having a coal plant, and you’ll be recreating the trials and tribulations of China’s Great Leap Forward. (Spoiler Alert—super dangerous, don’t really do this—EVER. It’ll likely kill you, your family, and most the flora and fauna within reach).
The way you can actually save money with solar energy, though (which the subsequent post will be all about) is through (a) subsidies and (b) grid tie-in agreements, under which the utility pays you when your panels are producing. You’re tied into the grid and essentially a remote power generator for them. The first is a way to largely offset the costs. The second one helps pay for the energy even quicker than you would be saving it. It also keeps you from having to buy costly batteries to store the energy. Unlike most things in life, electricity has to be used immediately or stored (which is expensive).
The way it usually works is that while you’re at home in the early mornings and in the evenings, your panels are producing zero—they’re not doing squat. But when you’re out of the house during the day, those bad boys are working like any other electric generator to produce power. The utility pays you during the day for the energy created at your house, and then you buy back energy from the grid when they’re not running.
There’s one even quicker way of making your money back through solar energy, but it really only makes sense if you need a new water heater. Solar water heaters have around a 10-year return (again, more on that in the follow-up), but you need to replace the conventional water heater, as well. Even in the dead of winter, these water heaters can heat up your tank considerably, and then your conventional water heater gets it the rest of the way to the temperature you want. There are several different types of systems, which you can check out here and here.
Whether you use solar PVs for electric generation or solar water heaters, there’s also some red tape. Some installers do all this for you. But if you buy the panels yourself, you’ll have to get both a building permit and en electrical permit, as well as a plumbing permit if you’re using solar water heaters.
Solar PV, in particular, is more wide spread in the States. It usually offsets a large part of your energy bills (on top of being a really cool conversation piece). There are several different ways of getting them installed, some as simple as making a call and scheduling an installation with no money down and instant savings. But the slightly more involved ways usually save you even more money along the way. Next time I’ll walk you through all the ways of making some scratch from your rooftop.