Solar power, intermittency and energy storage
Scalable energy storage is needed to complement abundant renewable energy power. Source here.
Some renewable energy solutions can scale from benefiting a single person to helping entire communities or small cities! One of the most fascinating insights I had early on this renewable path was realizing that the same fundamental decisions I am making about my own personal energy choices relate directly to much larger choices we are making around the world.
This is most obvious with solar power, specifically the use of inexpensive solar panels to generate electricity from the sun - but more significant when those panels are paired with batteries for storing excess energy.
BioLite solar panel charging its own (built-in) and external batteries. Source here.
I first started experimenting with solar powered electricity by purchasing several small/portable and ruggedized panels. I was intrigued with the idea that you only needed to invest in the panel once and then it would continue to deliver returns for the rest of its life. These panels were easy to use in camp (during the day of course) and on longer hikes where I would strap them to the outside of my pack. Sometimes, I would even run the USB charging cable from the strapped on panel straight to the phone in my pocket so I could trickle charge as I walked.
The beautiful feature of these particular panels and the reason I credit BioLite in particular for my growing interest in solar is that their product folks built a battery in to the device itself. So not only can the panel be used to charge external devices (including other batteries) in real time while the sun is shining but it can also store excess energy itself, which can be used later.
It wasn’t until later, when I started researching and buying larger panels that I truly began to appreciate the clever combination of power generation and power storage. Most panels are only capable of converting the sun’s rays into electricity on demand and must be paired with a separate battery to store energy for later use.
THIS TURNS OUT TO BE VERY IMPORTANT IF YOU WANT TO TRY LIVING OFF THE GRID!
I’ll skip over the subsequent solar power experiments which include buying an inexpensive 100 watt kit from Harbor Freight and how I paired that (crudely) with a deep cell marine battery for a multi-week long road trip. And how I ultimately upgraded to a more refined version of this combination from Jackery.
The key takeaway from all these options is that solar power - and this holds true for wind and even some renewable hydro power options - is unreliable. This may seem obvious in that the sun is only up in the sky for a certain number of hours in a given day. But, the larger picture for solar has even more variables:
On an overcast, cloudy or rainy/snowy day, there might not be any usable sunlight for your panel(s) so you are basically out of luck!
Your available sunlight might vary wildly based on where you are in the world and the surrounding topography - think about towns in the very far North or South of the planet or of cities that lie deep in a valley where the sun can’t reach for much of the “day”
The changing seasons will also affect how much sunlight is available even in the same city - in Chicago, our winter days are always “shorter” if you measure the time from sunrise to sunset
The appropriate and somewhat sobering term that the industry associates with solar and wind power is intermittent. Many clean & renewable energy sources are plentiful in concept but they must also be treated as unreliable. This is one of the primary reasons that we continue to use coal, natural gas and even nuclear options for our power - because we can reliably fire up these kinds of power plants when we need energy. We can’t (yet!) do this with solar and wind so we are forced to complement these relatively abundant power sources with cheap and effective storage solutions that can hold on to the energy when the sun goes down or the wind stops blowing.
It turns out that this exact combination is being used more commonly throughout the world to provide clean, more resilient electricity options for families and communities that don’t otherwise have access to a major power grid. Independent, micro grids have emerged as a viable option for lighting homes, charging phones and other devices and even powering local telecommunications infrastructure. These are truly life-changing developments that directly address the global issue of energy poverty.
A remote village is capable of providing its own power generation and storage. Source here.
I will dive deeper into these topics in upcoming articles, but if you’re curious about trying to go off-grid and supply your own electricity from seemingly attractive renewable energy options like solar panels, you will quickly gain an appreciation for the inherent challenges of intermittency and the value of reliable power from (battery) storage. You will also get closer to understanding how similar those challenges are for millions of people around the world who currently live without access to reliable electricity.