My own sobering solar power story

I seek out opportunities to escape into the remote wilderness for extended periods of time, and because I still use all sorts of electronic devices when I'm off-grid, I require a reliable way to charge my gadgets. I thought I had solved everything when I first bought large, durable solar panels for my excursions but after too many, unexpected cloudy days, I realized I had to expand my thinking. I knew my truck would provide sufficient charging power (e.g., USB ports/inverter), but I didn't love the idea of unnecessarily burning gasoline just to create electricity.

*The inconvenient solar power equation: off-grid + solar panels - sunlight = no power :(*

It was certainly convenient to be able to quickly start my vehicle and let it idle while I waited to charge the laptop, phone, headlamp, portable speaker, hoverboard (what?), etc. That instant-on power made me feel more secure for sure, but it also made me question what I had convinced myself about the practicality of living comfortably on solar power alone.

To get to the figurative & literal place I wanted to be, I ultimately had to learn about energy storage. It wasn't part of my original, nay beautiful plan to harness the free, abundant solar rays and be self-sufficient. We'll come back to my story in a bit (it has a more expensive - but happy ending).

Why this is your story too

I bring you this story because it affects you as well or will soon. The truth is that it is playing out all around us, at every scale of the Energy Transition.

In your neighborhood or maybe in your own home for example, solar roof panels are being paired with giant batteries to create more resilient renewable energy systems.
At the other end of the spectrum, the major utilities are having to incorporate long-duration storage resources as they increasingly incorporate renewable energy into the power grids.
And in local villages throughout the world, new microgrids are being created by combining solar panels with large batteries to introduce electricity to entire populations that had previously been deprived of this basic infrastructure service.

A remote village is capable of providing its own power generation and storage.
Source *here*.

Whether or not you have ever thought about where your electricity comes from, if you are on board with the clean energy transition, you will need to understand more about the inconvenient truth behind the intermittency of solar and wind power.

For many of us electricity is just like water

Here in the United States and indeed in many other countries, we have gotten quite used to the consistency and predictability of electric power. When we flip the switch on the wall, the lights come on. When we open the freezer, we know the ice cream will be cold. When our phone is low on battery power, we can recharge it in any nearby socket. It's the same as turning on a water faucet.

I do recognize that some communities encounter occasional brownouts and blackouts and that some regions are more susceptible to temporary power outages due to extreme weather-related incidents for example. But these are (for now) exceptions to the rule when it comes to reliable electricity.

This shared expectation of always-available electric power, something on which we collectively have become so reliant, is no accident. The entire system is designed to be dependable for consumers and a big part of that plan is tied directly to the methods we have used to generate the power. In their book, Our Renewable Future, authors Richard Heinberg and David Fridley call this out:

Power engineers designed our current electricity production, distribution, and consumption systems around controllable inputs (hydro, coal, natural gas, and nuclear)

As the energy industry has evolved from generating hydro power from existing waterways to burning coal and then natural gas to having mixed success with splitting atoms, all of their methods share the one key characteristic that we (humans) could mostly control the generation side of the system. And that control is key because it ultimately leads to more consistency and better predictability for creating electricity.

Here comes the sun (and wind)

The general public is also simultaneously getting more familiar with renewable energy sources showing up all around us. We are used to seeing solar panels on individual rooftops. We often getting distracted by the prominent solar farms stretched out across acres of sun-drenched land off the side of the highway. And it is certainly hard to ignore those gigantic, stark white and not exactly discrete wind turbines dotting the landscape - is it me or do they always seem to be spinning too slowly to be doing anything productive? :-)

And I personally hope that these novel structures eventually become as commonplace and familiar to us as telephone poles and transmission power lines. But there is one major difference with these new entrants to the electricity landscape.

We can't control the Sun or the wind!

As we expand the use of renewable energy sources like wind and solar power, we are having to acknowledge and work around the challenges of intermittency. In short, the sun *does* rise every day but we simply can't count on year-round sunny days to convert photons into electricity. And similarly, even in the windiest places, we can't rely on the strength or duration of that wind flow.

Most (but not all) renewables differ from preceding energy sources like oil, gas, coal and nuclear which are not renewable (per se), but do lend themselves to more predictable, reliable and consistent power generation. This, along with a longer track record of being able to manage their relative costs is why they have become so prevalent and will be difficult to replace quickly.

I mention the two most popular/viable forms of renewable energy but even the "dirty" fossil-fuels are technically renewable. The problem is we have been depleting these natural resources far faster than the Earth can renew them. In a little more than 100 years, the industrialized nations have consumed the lion's share of planet's stored energy - a collective stockpile that took millions of years to form as oil, natural gas and coal.

This unpredictability of ideal natural conditions is a big problem for our necessary conversion over to clean energy. While abundant solar and wind power sounds more attractive, the inconvenient truth is we don't have a solid plan for incorporating new power generating resources that we can't control. With a traditional, fossil fuel fired power plant, we can flip a switch and produce power reliably, on-demand. The energy system isn't (yet) ready to deal with concepts like variable availability, or sources that are non dispatchable.

Reliable >> Renewable

When you step outside of industry conversations and engage the everyday energy consumer, you can likely start a productive conversation about renewable energy, but you won't hear much talk about reliable energy. But as we wait for more solar and wind (and other clean energy types) to come online, we need to expand our understanding of what the next iteration of our power infrastructure looks like.

After decades of investment spent to nearly perfect the process of pulling oil, gas and coal from the Earth and converting those into usable energy, we've become accustomed to electricity just being there when we need it. You and I have not had to understand that this modern convenience is all based on our ability to control the production of power.

We can get frustrated at price fluctuations in gasoline for our vehicles or spikes in our monthly home power bills but aside from extreme weather events or freak accidents, we don't question the reliability of that electricity from the utilities.

So, the renewable elephant in the room then, is that the solar and wind power will not be able to produce the same reliable energy to which we've become accustomed. What does that mean for the future of clean electricity?

Achieving reliable electricity through energy storage

The prevailing wisdom is that we need to supplement abundant but unpredictable renewable energy sources with large-scale energy storage systems (i.e., batteries) that can store and later "generate" electricity on demand when the sun goes down and the wind stops blowing.

In my own off-grid story, I decided to purchase a portable "power station" device, which is just a fancy term for giant battery. I can charge the power station from my solar panels when the sun is out and then if needed, plug my devices into its ports if I need electricity at night. Alternatively, I can charge the battery from any conventional/convenient wall outlet and also from the truck's cigarette lighter ports too!

I have early adopter friends who have taken this exact approach with their rooftop solar panels. There is a growing number of manufacturers who can install large (non-portable) batteries at your house that seamlessly and reliably provide electricity if/when the grid-supplied power is disrupted. They too are charged using excess power from the solar panels and thus create a more predictable electricity solution for your home.

*Depiction of Tesla Powerwall battery system that complements rooftop solar panels*

Commercial and industrial scale energy storage

Companies and governments are working to develop and scale up complementary energy storage systems (ESS) that will store energy, typically when it is abundant, and they use that stored energy when the original source is unavailable.

By combining (local/convenient) energy storage with renewable energy supply, we have found a way to increase the reliability of clean but unpredictable power supply sources like solar and wind. So, while we may not (yet!) completely control the Sun and the wind like we have mostly managed to do with coal and natural gas energy sources, we can effectively achieve a similar result.

All over the world, we are seeing the introduction of exciting, large scale battery solutions that do more than just compensate for an occasional overcast or low wind day (variability). They are thinking much bigger about this problem. For example:

How do we accommodate shorter Winter days where there is less available sunlight than on the longer Summer days (seasonality)?
How do we acknowledge the differences season to season so we can effectively store surplus energy for an entire season or two?
How can we unlock massive new energy stores using innovations like vehicle-to-grid technology that could aggregates the power stored in hundreds of otherwise idle electric vehicles?

Non-intermittent renewable energy sources

Here I have only focused on solar and wind power but not all renewable energy sources present the same challenges with intermittency and unreliability. It is worth mentioning for example that the world has a much longer track record with hydro-power both for generation and storage.

Hydro power (from flowing water) is somewhat predictable and certainly more controllable through the use of hydroelectric dams, but as a power source it is limited in terms of where it can be deployed. As with other stationary power generation options, there are methods for getting the power closer to where it is needed by that requires transmission lines which add another variable and a potential source of failure.

And if you are interested in how water can also be used as an energy storage solution, I invite you to read my article about pumped-storage hydro power here.

One other promising but less frequently discussed clean, renewable energy alternative is geothermal energy that taps into the immense source of heat under the ground to ultimately turn electricity-producing turbines. There is an excellent primer on geothermal from Energy Reality that provides more detail:

Unlike wind and solar energy, which are intermittent sources of power, geothermal energy is consistent, and thus is one of the only renewable energy technologies that substitutes well for coal generation. (Coal power plants take hours to become hot enough to produce electricity efficiently, and then hours again to cool down—so plant operators try to use coal plants as always-on baseload power to decrease wasted energy during the start-up and shutdown periods.)

Pulling energy from inside the Earth would seem to be more predictable although it may not be practical to drill through the bedrock in your own backyard to tap into this abundant geothermal supply.

Closing thoughts

As I've been researching renewable energy topics, I am continuously surprised at how big this space is and how much there is to learn. To appreciate the viability of replacing coal and gas electricity generation with cleaner options, I needed to first acknowledge what made those previous forms attractive and recognize how challenging it would be to transition away from them. Aside from the billions of dollars we've spent on trying to optimize and perfect fossil fuel discovery, extraction, transportation and ultimately power conversion, there is the universal comfort level that we have cultivated with having blanketed much of the planet with reliable electricity. That should not be underestimated by climate conscious advocates.

Addressing the inconvenient truth about intermittent renewable energy