132 thousand residential solar jobs with caveats
In our editorial a fortnight ago, on January 27th, we raised questions about the widely reported and cited number of residential solar jobs. The source, The Solar Foundation, has now graciously provided considerable detail on the number and the survey that was used to estimate it.
The findings of the latest annual survey of The Solar Foundation were published last month in the “National Solar Jobs Census 2015.” The report states there are 209 thousand solar jobs. Of these, 132 thousand are in residential solar.
The president and executive director of The Solar Foundation wrote us on January 29th, two days after our editorial, to address the questions we raised. We then asked for further detail on February 2nd. The Solar Foundation addressed this follow-up on February 4th.
The Solar Foundation pointed out that not all residential installation jobs are involved in solar roofs to generate electricity. Fourteen percent of the jobs are involved in installing solar thermal, heating/cooling, pool heating, etc. So the number of solar roof jobs are 10,577 less than a reader of the report might have assumed.
The Solar Foundation also pointed out that the percentage of residential installation jobs that are full-time is lower than the ninety percent the report estimates for all solar jobs. Eighteen percent of residential installation jobs are part-time. So the number of full-time solar roof jobs is down to 53,837, again less than a reader of the report might have assumed.
Most importantly, The Solar Foundation pointed out that just two-thirds of full-time solar roof jobs are installers. What about the other one-third of the jobs? They’re in overhead and administrative functions, so the number of full-time solar roof installers is merely 36,000.
That’s less than half the number that a reader of the report might have assumed, 48 percent to be exact. As many as 39,556 jobs are not full-time solar roof installers.
In our editorial a fortnight ago, we did a sanity check of the number of residential solar installers, comparing it to the number of residential solar installations. With the number of installers reduced by The Solar Foundation by 52 percent, the installations per installer productivity figure should become more understandable.
Our editorial assumed that residential solar was installed at 300,000 homes last year. Does anyone know how many installations there were? Suppose 1.8 thousand megawatts were installed and the average installation was six kilowatts. That’s 300,000 installations.
We’d come to the same installation activity if 1.5 thousand megawatts were installed and the average installation was five kilowatts. Still seems like 300,000 installations is in the ballpark.
But let’s go the extra mile and use a higher level of installations, 360,000. This level of activity has the benefit of making the calculations nice and round.
Last year, there were then 360,000 installations and 36,000 full-time solar roof installers. Divide the second value into the first and you get ten installations per installer per year.
If two full-time installers work on a residential solar roof installation, then each team of two installers does twenty installations per year. That’s one installation every eighteen days. A typical installation is said to take a couple of days or so.
If three full-time installers work on an installation, then each team does thirty installations per year. That’s one installation every twelve days.
Either way, it still does seem that the productivity of full-time solar roof installers is mysteriously low. That could be the case, that their productivity is indeed low. Or it could be the case that the jobs number of 36,000 remains unexpectedly high.
Productivity would be worse if we took into account that, per The Solar Foundation, there are 11,142 part-time solar roof installation jobs, most of which are installers. They certainly work on installations too.
One can’t question that the growing residential solar roof industry is providing a growing quantity of jobs. But how many? We continue to want estimates to be used with appropriate circumspection and caveats.
Our appreciation again to The Solar Foundation for graciously providing more detail on its jobs number and the underlying survey.
Steve Mitnick, Editor-in-Chief, Public Utilities Fortnightly
E-mail me: mitnick@fortnightly.com
