Solar technology has come a long way since its beginnings in the 1950's. New technologies and manufacturing methods have drastically improved efficiency and lowered cost over the years, allowing homeowners who want to go solar to spend less money, and produce more energy with fewer panels. Due to this progression of falling prices and higher efficiencies, homeowners who are researching solar may think that waiting until the technology is even better will provide them with a better return on investment. The question is then, how fast is solar technology actually improving and is it worth waiting for better panels to be released?
The original solar cell as we currently know it was invented and patented in 1954 by D.M. Chapin, C.S. Fuller, and G.L. Pearson of Bell Laboratory. The silicon-based cell they made was the first of it's kind due to its stability and reliability, but its efficiency was very low at 4%. Shortly after, another company, Hoffman Electronics invented the first solar panel for sale to the public, at a steep cost of around $1,785 per watt, with cells at only 2% efficiency. Today, with inflation, that would be around $16,000 per watt, an abomination compared to the $4 a watt we are actually paying now.
Solar Goes Mainstream
The 1970's and 80's saw an explosion of utility-scale solar due to government intervention. The Environmentalist movement, and an energy crisis brought on by the Arab Oil Embargo, prompted the US to enact The Public Utility Regulatory Policy Act and the Energy Tax Act of 1978, which provided large tax credits to homeowners who added energy efficiencies to their homes, as well as a framework for solar interconnections. This sparked the creation of the first utility-scale solar farms, which not only made the idea of solar go mainstream, but attracted investment money into photovoltaic research and development.
Due the influx of research funds in the 1970's and 80's, the race to the highest efficiency began and has not ceased. Notable benchmarks over the last three decades included:
1992: University of South Florida makes a 15.89% efficiency thin-film cell.
2012: Solar Frontier releases their 17.8% efficiency panel
June 2015: First Solar makes a 18.2% efficiency panel
October 2015: Solar City reaches 22.04% efficiency, shortly after Panasonic reaches 22.5% efficiency
November 2015: SunPower reaches 22.8% efficiency
June 2016: SunPower creates 24.1% efficiency module
So the rate at which efficiencies have gotten better has actually slowed over time, and unfortunately, they can't get that much higher. The reason is that crystalline silicon solar cells have an efficiency ceiling of around 29% and realistically because cell efficiency is higher than module efficiency, the maximum panel efficiency is around 25%.
So for those homeowners who are sleeping on solar because they think the efficiency is going to get way better, they are unfortunately waiting on somewhat minimal gains, all the while still paying the utility for their electricity.
Contrary to efficiencies, prices of panels have fallen significantly even in the past few years. In 2015, price per watt fell around 4.5%, and in 2016 prices fell another 10%. This decline is mostly due to the importing of cheap Chinese panels, but rebates and higher demand have also driven them down.
Homeowners researching solar may consider pushing their installation back when faced with these declining prices, but there are other forces at work that could work against those prices in the future. The Federal Solar Tax Credit, for example, is being slowly phased out in the coming years, and the potential solar tariff on imported panels may equal out the price declines. There's also the fact that the longer you don't have solar panels, the longer you are paying the utility and not yourself.
The reality is that solar panels are already efficient and cheap enough that you will likely recoup your investment in less than 10 years. The efficiency of SunPower panels is such that you will be zeroing out your power bill, even at the current efficiency. Unless you want to wait so you don't have to get as many panels, there is no reason to delay your solar installation for panel efficiency reasons. The amount of money you will save by going solar now will be more than the small additional amount you will save by waiting for solar panels to be more efficient.
So if you've been waiting to go solar because you think you will save more money with a higher efficiency panel, or with dramatically lower prices, you're waiting in vain. Going solar sooner than later will always end up saving you more money in the end, as even with falling prices, not having to pay your power bill sooner will ultimately save you more money. So stop waiting. Make the solar leap today.
SunPower by Stellar Solar
265 Via Del Monte
Oceanside, CA 92058