Solar Cell Efficiency vs Solar Panel Efficiency

In your research trying to understand solar power, you feel like solar panel efficiency is something you should be able to easily grasp. Efficiency should be easy to understand, right? Except the deeper you dig, the more confused you get. What’s the difference between solar cell efficiency and solar panel efficiency? Who can you trust when it comes to solar efficiency?

I got an email from someone purchasing solar panels from a supplier asking the difference between these two efficiencies. Helping people understand questions about solar is the whole point of this website, so after I answer a question via email – it often ends up here so that more people can learn.

Here’s the question:

My prospective supplier states that the Schuco 210 watt SMAU-1 panel has a cell efficiency of 16.8%, whereas your table gives a panel efficiency of 14.93%. What is the difference between panel and cell efficiency and which should be my guide?

5 Questions to Ask Before Purchasing a Solar Electric System

This is an edited excerpt of an article originally posted on AOL Real Estate written by Audrey Tempelsman. Audrey asked me to help her on an article you can read in full here.

There are a nerve-wracking number of solar manufacturers and installers out there, so I caught up with Shawn Roe of SRoeCo Solar, a solar advice service, and asked him to share five questions that all consumers should ask before purchasing a system. I hope you’ll find his insight as helpful as I did:

1. “How many systems has your company installed?”
Due to the recent spike in solar panel installations, and the decrease in other construction-related businesses, many roofers, fencers, and builders are attempting to start solar installation companies with no solar experience and without proper solar installation knowledge. Look for a reputable installer with at least 50 installations and a few references.

How to Get Free Solar Proposals

There’s no better time to get solar panels installed on your home or building. Despite the drop in gas and oil prices in late 2014, solar is still the future. Get in while it’s hot (pun intended). The founder of PayPal, SpaceX, and Tesla Motors, Elon Musk, is confident that “solar will beat everything, hands down, including natural gas.” Elon is basically our modern day Nostradamus / Ben Franklin.

The only question now is, “where can I get solar panels for myself?” When people ask me, I always recommend that they contact a handful of solar installers in their area and pick the one they trust most. Some people don’t know how to get free solar proposals. It’s as easy as contacting a solar installer. But which solar installer should you contact? I’ve put together a short list of some of the largest and most reputable solar installers that operate nationally (*well, in a bunch of states at least). These are the solar installers I’d recommend to my friends and family, so I might as well recommend them to you too.

Top 20 Most Efficient Solar Panels On the Market

Are you looking for the most efficient solar panel available in 2014 to put on your roof? Here are the top 20 most efficient solar panels actually available for sale (on the market) – not just tested in a lab. All of these modules (solar panels) are eligible for incentives in California, which means they’ve been tested and have a minimum 10 year warranty against defects and undue degradation.

This is an image of the top 20 most efficient solar panels in a chart by SRoeCo Solar.

Solar Panels are Cheap Enough and Efficient Enough

Solar panels are too expensive and not efficient enough? In 2014, that’s no longer true.

Solar panels are cheap enough and efficient enough. Renting your electricity from a utility for the rest of your life is no longer the only option. If you invest in a solar panel system, you will be your own utility and can start earning a return on your hard-earned money. (Oh yeah, and you’ll be helping the environment and future generations while you’re at it.)

Solar Prices Falling

Every week there’s another article claiming that solar has “two fundamental problems…: they’re not very efficient, and they cost a lot to produce.”

I disagree with both of these. First of all, solar panels are currently plenty efficient to produce valuable energy. If not, why would so many governments invest in solar (from the US to China, Germany, Spain, Japan, Korea, even Namibia and Morocco).

There is a myth that solar is getting more efficient every year and that people should wait for next year. This is a myth. Solar efficiency does not follow Moore’s Law – efficiency does not double every X years. So, no need to wait. It’s efficient enough right now.

As for the claim that solar costs a lot to produce – the cost of solar has dropped “60% since the beginning of 2011″. Does solar cost more than burnable substances dug up from the Earth? In many places, where oil and gas companies are subsidized, yes. But that doesn’t mean solar is too expensive to use. On the contrary, solar is so cheap that it’s an obvious financial investment for many intelligent business and home owners.

If solar panels weren’t efficient enough, or cost too much, then for-profit companies and millions of homeowners around the world would not be installing solar.

Solar panels, at their current efficiency levels, have the capability to produce more than enough energy to power the entire world 46 times over just by putting solar panels in the unpopulated parts of the Sahara desert. And solar panels are cheap enough to get a ROI good enough for Google, Wal-mart, IKEA, Johnson & Johnson, FedEx and millions of businesses and homeowners around the world. For-profit businesses and the typical homeowner wouldn’t install solar if it wasn’t cheap enough to be a good value.

Top Companies with Solar

Solar panels suffer from two fundamental problems: (1) the general public is uninformed about the economic and environmental benefits of solar, and (2) the current system of energy based on fossil fuels and limited resources is fighting against the adoption of solar to protect the status quo’s financial interests.

Solar panels are both cheap enough and efficient enough now.

Why Fossil Fuel Companies Don’t Fail like Solyndra

I recently engaged in a friendly debate online on the merits of renewable energy versus fossil fuel energy, and the other side once again brought up Solyndra as a reason why solar companies aren’t as financially viable as fossil fuel companies. I have an idea why gas, oil and electric companies don’t fail like renewable energy companies. Maybe we haven’t heard about failures of gas, oil and electricity providers because they receive so much more government support compared to renewable energy companies.

This is an image of a chart comparing fossil fuel subsidies to renewable energy subsidies.

I believe that governments should invest in renewable energy technology (mainly solar), as well as support laws that allow for the fair competition of renewable energy with current means of energy production (mainly fossil fuels). Currently the subsidies and laws are skewed to favor oil and gas companies and electric utilities (who often act as local monopolies). This is unfair, anti-competitive and should be corrected.

Top 26 Most Efficient Solar Inverters

Of the top 26 most efficient solar inverters 20 are SMA inverters. Only 26 individual solar inverters are rated at either 98 or 98.5% efficiency (which is the highest efficiency for inverters). SMA has been around since 1981 and seems to be the clear leader in manufacturing top-of-the-line inverters for solar applications.

Top 26 Solar Inverters Chart

Top 10 Most Popular Solar Panel Manufacturers

There has been a shaking out period going on for a while in the solar industry. Big names like BP and Bosch have dropped their solar divisions, while other companies have just gone under like Konarka and of course, Solyndra (which never really was that big).

Well which manufacturers have not only held on, but are the most popular for solar installations in America’s largest solar market? We’re only looking at the last 2 years plus the first quarter of 2013. So that’s Jan 1, 2011 to Apr 17, 2013.

Solar Panel Efficiency and Life

So, the Sun shines on Earth and in that sunshine there is energy. Plants convert that energy into mass because energy is mass. E = mc2. Energy equals Mass times a constant (which is not important here). We eat the plants for energy, or we eat animals that eat the plants. That’s how we survive.

Simple Explanation:

Well, solar panels are humans’ attempt at making “plants” that convert the Sun’s energy into energy we use – to heat, chill, or light our homes, to power our TV’s, fridges, computers, etc. Well, it’s not easy converting that sunshine into energy we can use. And as it turns out, most solar panels convert 12-15% of the Sun’s energy that falls on the panel. The Sun dumps ~1,000 W/m2 at sea level on a clear day (source: wikipedia).

Australian Solar Credits, STCs, and FITs

So you’re thinking about installing solar on your roof in NSW or Queensland, huh? The Aussie government promotes ‘green initiatives’ and will help you financially, but they haven’t made it easy for you.

Solar Credits and STCs

First of all, you get ‘Solar credits’ for installing eligible solar systems in Australia. The credits are simply multipliers for renewable-energy incentives called STCs (or Small-scale Technology Certificates). What the heck is that? Well, it’s probably like a coupon or a gift certificate that you can redeem for cash (or tax credits), right? Wrong. They’re more like green energy stocks that are traded among registered agents or on a specific market called the ‘Clearing House’. What the heck is a registered agent? Maybe your installer. But maybe not.