For some reason, the most plentiful, easiest to access, and environmentally friendly form of energy is one of the least used in the US (less than 1%). Solar provides less energy on a global scale than hydro or wind, yet it has a lower impact on land and the environment. Man-made reservoirs waste water in evaporation and are very expensive. Wind turbines can be considered unsightly and harm wildlife and potentially weather patterns. Both of these sources must also be located a good distance from the customers they are serving. Why then is solar viewed so negatively? Here are three myths that should be dispelled about solar power.
1. Solar is inefficient
Photovoltaic solar from cheap and common silicon panels have a maximum theoretical efficiency of about 19%. This can get up to 44% with optical concentration and multi-junction cells, but that is new technology in its infancy. Even with only 20% efficiency, solar is not much worse than conventional power from large plants. The math is actually pretty simple.
Therefore, in optimium conditions fossil fuel energy is only about 7% more efficient than solar. That is not really a huge difference when you factor in the costs to create, transport, and manage a large grid when compared to local solar installations that feed directly into the end load.
2. Solar is expensive
In 2014, you can buy a 5kW solar system that is enough to create a net zero typical american home is for less than $15,000 in total. This represents about 45 months of energy bills (at around $200 per month). It is pretty easy to see that there is no longer the "20 year payoff period" that we had in the 90's and early 2000's. With payoff in under 5 years (and even lower if you build a new house with solar), and tons of financiers jumping into the industry it is now possible to go solar even if you don't have the cash on hand. In addition, solar panels are getting cheaper every day.
3. Solar Won't Work for My House
"I don't have south facing roof space." "I have too many trees." These are excuses that I have heard many times, but the greatest advancement in solar power in the last 5 years isn't one that most people have heard of, and it counteracts these concerns. I am talking about micro-inverters.
Photovoltaic solar panels produce DC power. Every home in the US is designed to use AC power because it travels better and can be used more easily by motors (1/3 of all energy consumption). This means the energy needs to be "inverted" or transformed from DC to AC in order to be used.
Most solar systems installed until about two years ago used systems where many panels were connected together and then one large, expensive inverter transformed all that power and stepped it down to the common voltage and amp levels used in the home (110V, 60Hz). In addition to being less reliable, this also means that any decreased performance in any single panel DECREASES PERFORMANCE FOR THE WHOLE SYSTEM! This is why many people thought they couldn't get solar.
Micro-inverters take advantage of advances in electronic control systems to shrink the inverter so that there can be one on every panel, thus maximizing the output of the system whether there are trees, clouds, or dirt on any single panel. In addition, these systems are more reliable and cheaper to install (run less wires through the house).
Finally, this doesn't even take into account the tax and other incentives available almost everywhere, including the 30% Solar Investment Tax Credit. This could make the payback period even shorter.
Solar makes sense. Especially as we get better storage technologies to match the energy consumption to production, but that is a discussion for another post!
1. Solar is inefficient
Photovoltaic solar from cheap and common silicon panels have a maximum theoretical efficiency of about 19%. This can get up to 44% with optical concentration and multi-junction cells, but that is new technology in its infancy. Even with only 20% efficiency, solar is not much worse than conventional power from large plants. The math is actually pretty simple.
- Large fossil fuel generators are about 40% efficient in converting the energy of the fuel to electricity.
- The transmission lines are about 75% efficient in optimum conditions
- Transformers and substations are 90% efficient in total.p
Therefore, in optimium conditions fossil fuel energy is only about 7% more efficient than solar. That is not really a huge difference when you factor in the costs to create, transport, and manage a large grid when compared to local solar installations that feed directly into the end load.
2. Solar is expensive
In 2014, you can buy a 5kW solar system that is enough to create a net zero typical american home is for less than $15,000 in total. This represents about 45 months of energy bills (at around $200 per month). It is pretty easy to see that there is no longer the "20 year payoff period" that we had in the 90's and early 2000's. With payoff in under 5 years (and even lower if you build a new house with solar), and tons of financiers jumping into the industry it is now possible to go solar even if you don't have the cash on hand. In addition, solar panels are getting cheaper every day.
3. Solar Won't Work for My House
"I don't have south facing roof space." "I have too many trees." These are excuses that I have heard many times, but the greatest advancement in solar power in the last 5 years isn't one that most people have heard of, and it counteracts these concerns. I am talking about micro-inverters.
Photovoltaic solar panels produce DC power. Every home in the US is designed to use AC power because it travels better and can be used more easily by motors (1/3 of all energy consumption). This means the energy needs to be "inverted" or transformed from DC to AC in order to be used.
Micro-inverters take advantage of advances in electronic control systems to shrink the inverter so that there can be one on every panel, thus maximizing the output of the system whether there are trees, clouds, or dirt on any single panel. In addition, these systems are more reliable and cheaper to install (run less wires through the house).
Finally, this doesn't even take into account the tax and other incentives available almost everywhere, including the 30% Solar Investment Tax Credit. This could make the payback period even shorter.
Solar makes sense. Especially as we get better storage technologies to match the energy consumption to production, but that is a discussion for another post!
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