Over the past year, we’ve witnessed terrible accidents in “the big three”energy sectors: the Massey coal mine explosion in West Virginia, whichkilled 25 miners; the explosion of the drill rig Deepwater Horizon,which killed eleven and caused billions of dollars of damage; and the on-going nuclear crisis in Japan, which is prompting many to reassess the probability that a similar disaster occur here in the United States.
If anything is clear, it’s that there are risks associated with theextraction and production of energy — and that all sources of energycome with costs and benefits.
With that in mind, let’s take a quick look at the benefits and costs solar photovoltaic (PV) energy.
First, the benefits:
- Solar PV power is reliable. Year over year, theamount of sunlight that hits your roof doesn’t vary that much. Thismeans that it’s easy to predict how much electricity your system willproduce over the course of its lifetime (and how much you’ll save onyour monthly electric bill — see next point). In fact, some solarinstallers even offer power production guarantees: if your solar energysystem doesn’t produce the annual production stated in the contract,they’ll pay you the difference.
- Solar power lowers your electricity bill. We findthat most homeowners and business owners who install solar panels do soto offset their usage of conventional electricity. Where the price forgrid power is high — like California, Hawaii and much of the northeast — solar panels are particularly good at slashing monthly electricitycosts. And, thanks to net metering, any extra power you produce in, say, June shows up as credit on your July electric bill.
- Solar PV is safe and clean. After accounting forthe energy used to manufacture the panels, solar energy systems produceemissions-free electricity, which definitely cannot be said ofcoal-fired power plants. And, unlike nuclear power, there’s noradioactive waste to deal with… which is nice.
Now, we’ll be the first to admit that solar PV can’t do it all. There are limitations:
- Solar is a variable energy source. While solarproduction is predictable on an annual basis, the same can’t be said for a daily or even weekly basis. No matter how much you may want it tohappen, your solar panels just won’t produce electricity at night.Luckily, net metering helps smooth out your production/consumption ofelectricity. It’s fairly common for a PV system to run the home’selectric meter backwards during the day; at the end of the day, when the family returns home and the sun goes down, the meter then spins in thenormal direction. (The variable nature of solar power has biggerimplications for PV’s use at the utility scale because utilities can’tuse solar to easily “dispatch” electricity at a moment’s notice orgenerate power at night.)
- Without incentives, solar is a more expensive alternative. The federal government offers a tax credit worth 30-percent of totalinstalled system costs. Beyond this, some states offer solar rebates,tax credits and other incentives to help homeowners and businesses makethe transition to solar power. Some programs are so good that residentsin these areas would be silly not install a solar home energy system. As a general rule: in the absence of (a) state incentives, and/or (b) high electricity prices, chances are good that solar PV is a relativelyexpensive option for you. This is changing all the time, as solar panel prices continue to fall and financing options like solar leases proliferate. So it’s safe to say that solar PV is becoming an affordable option for more and more Americans, every year.
- Some roofs just aren’t good for solar. For arooftop system to work well, you’ll need a roof that’s in good condition and gets unobstructed southern exposure. Trees and tall buildings arecommon sources of shade, and sometimes we have to tell folks that arooftop system just is not in the cards. Ground-mounted systems are great, too, but you’ll need sufficient space in your yard. Read more: What Makes a Roof ‘Good’ for Solar?
So, there you have it… This is by no means intended to be anexhaustive list. If you have comments, feel free to post them below.