19 April 2022 |

Making solar energy storage smaller ☀️


Everyday electronic gadgets like your phone, headphones, and smart watch are powered by lithium-ion batteries charged with electricity. Even if we manufacture trillions of them however, these batteries won’t be able to carry the entire load of electrifying the global economy however. Whether it’s large scale energy storage or small, different systems are needed.

Many exist on the large-scale front. Examples include pumped hydro, which constitutes 95% of utility scale energy storage in the U.S., or compressed air energy storage. We’ll dive deeper on all these soon.

At smaller scale however, e.g. at the level of electronics, other options are a) necessary and b) in development. Enter solar powered nano-generators.

Solar is famously intermittent, i.e. it’s only available for active power generation when sun is shining on the part of the planet you’re currently on. How to maximize storage of solar energy to tackle the intermittency challenge efficiently is and has been a major focus in R&D.

Excitingly, last week, scientists in Europe made some fresh headway. Back in 2017, a team led by Kasper Moth-Poulsen at Chalmers University of Technology (also part of Gothenburg University in Sweden) unveiled a potential energy system, specifically a ‘Molecular Solar Thermal Energy Storage Systems,’ to store solar energy for 15+ years. Post storage, their system released energy as heat. That alone is solid for all kinds of applications… like heating your home during a cold Swedish winter. 

The team received grant funding from the EU in 2020 to continue developing the tech. And now it’s paying off, even beyond just scaling the system for heating. Last week, they announced success in turning the stored energy into electricity by establishing a successful connection with a thermoelectric generator. The ability to turn the heat back into electricity makes the energy storage system even more flexible (more potential applications). 

A graphic rendering from an article in Cell Reports Physical Science

How does the tech work? It’s based on a specially designed molecule that consists of carbon, hydrogen and nitrogen. When it comes in contact with sunlight, the molecule changes shape and becomes more energy dense. The isomer can then be stored in liquid form for use when needed. To re-harness the energy, with the help of a catalyst, the molecule can return to its original shape, releasing the stored energy as heat in the process. This also renders the molecule and system capable of repeat conversion – once the molecule is back in its original form, it’s ready to change shape again when it comes in touch with sunlight.

For another angle / overview, check out this short video from the university. 

As we noted above, the big unlock last week was that the team successfully converted heat into electricity via thermoelectric generator. These generators aren’t like the ones in your backyard; they’re actually very small, ultra-thin chips. Which means this energy storage system lends itself to small-scale applications.

Coming full circle, it’s cool to see progress made designing alternative energy storage systems that not only work at large scale but at the scale of consumer goods and electronics. Innovation across the entire spectrum is necessary.  

As with lots of what we cover, this tech is very much still under development. But, it pairs nicely with an increasing focus of mine, which is on alternative energy storage systems.

Energy storage itself is going to need to scale massively in coming decades. And we’ll need ‘all kinds of kinds’ of storage for different applications and durations. Just today, the Rivian CEO opined that a future battery squeeze will make current supply chain shortages look like a “small appetizer.” Food for thought!

The sun is *not* yet setting on new drilling in the U.S.


Open season! … for new drilling on public land 📉. 

Showing zero love for upcoming Earth Day, the Biden admin recently opened 144,000 acres of public lands across nine states up to new oil leases and drilling. This of course comes amidst immense supply-side pressure on gas prices across the U.S. as Russia continues its war in the Ukraine and sanctions on imports for Russian oil and gas continue. In nearly the same breath today, Jen Psaki did say “we don’t feel they’re needed” with respect to new oil leases on public lands. So why open them? Weird bit of a double talk here.

The move did come with some new mechanics that will make it a bit less attractive to drill than it has been in the past. For instance, royalty payments that lessors need to pay back to the Feds increased 50%, from 12.5% to 18.75%.  

Look, I get. The admin is in a pickle here with gas prices and inflation overall where they’re at. The environmental and climate challenge is less about incremental barrels of oil however. Rather, once new oil & gas sites get up and running and the infrastructure is in place, it’s hard to close the door on them again in coming years. Investment and expansion in O&G is pretty sticky – how do you get companies who have invested a lot of capital to valorize energy assets to walk away from them? 

Pragmatism aside, this is also a clear failure vis a vis Biden’s campaign promise not to open any more public lands for drilling. Desperate times call for desperate measures… but what’s more desperate? Sky high gas prices or the emissions reduction progress the world needs to make by 2030?


Drum roll please… OK, not quite ready yet. I’m stoked to unveil episode 6 of the Keep Cool show very soon. We’re taking our time to make this special and hype it up sufficiently; it won’t be this Thursday. But it will be out by next week! Stay tuned. 

It’s been a journey hosting a pitch competition as a podcast mini series. I wouldn’t fault you in the slightest if you haven’t followed along with every episode; I know it feels like we’ve been at it for months (we have).

To catch up on all that’s happened… listen here

Episode 6 will be all about:

  • Reviewing the 5 teams we’ve had on the show
  • Hearing first-hand from my investor co-hosts which companies in particular they were most excited about, both a ‘pure’ pitch perspective and whose theories of change and climate impact could prove to be most impactful

A big part of the fun and learning for me? Hearing each investor discuss the rationale behind their picks. Some saw great investment theses in the businesses. Others tripled down on taking a lens of which solution they most want to see work for the sake of the climate.

All of this shines a useful light on what investment looks like in climate tech. It’s about more than the bottom line, or other fancy financial metrics people look for, whether it’s recurring revenue or dollar based net expansion.

Above all? It’s about reversing climate change. 

What will we do at the end? Based on all 5 investors’ votes, we’ll announce which team will take home a ton of media value from Workweek to supercharge the next phase of their company’s journey. Further, I’ll team up with them to write a deep dive on their business, going even deeper on some things that didn’t necessarily make it into a 30 minute podcast edit. + I may even invest in their business – tbd!


What I’m reading 📧: The Triple Bottom line! Hungry for more doses of sustainable start-up and business news? The Triple Bottom condenses hours of reading into a snappy 4 minute email. Perfect for staying in the know … for free.

What I’m listening to 🎶: Kurt Vile’s new album. On repeat. All week. Love it. Gonna go see him perform in NYC on June 2nd too. Join me! 

What I’m up to 🌊: Driving up the CA coast for the next few days! I’ll share lots of pics in upcoming newsletters.