Iceland Carbfix Tour

In July 2025 we took a tour of the Geothermal Exhibition at Hellisheiðarvirkjun in Iceland, all about Geothermal power. My spouse is a Professional Geologist, for whom this was an especially interesting tour.

We took a slightly more extensive version of the tour which included the CarbFix plant, a carbon capture and sequestration project where carbon dioxide is injected deep underground to mineralize.

Near the Carbfix injection site is the Climeworks Mammoth plant, a direct air carbon capture facility. We didn't get to go inside, we could only see it from a distance.

Steam pipes from the geothermal vents back to the power plant.

Steam pipes within the power plant.

Turbine within the power plant.

Climeworks Direct Air Capture facility.

Carbfix H2S+CO2 pumping facility.

Carbfix H2S+CO2 meters.

Personal View of NYC Congestion Pricing

In the 2010s I managed an engineering organization with teams in California and New York. I travelled to NYC a number of times, typically staying near Chelsea Market.

The Maritime on 16th street was my usual lodging, next to Google's NYC office and with the 14th Ave subway station nearby. I recall the blaring of car horns being ever-present, continuing late into the night.

We brought the whole family to New York City in July, the first time I have been there in almost 10 years. We stayed in Manhattan in the Financial District, and went for pizza very near the Google building. The streets were very clear, nowhere near the level of traffic I remember.

(view from the Empire State Building)

(on the way to pizza)

In January 2025, New York City implemented a congestion pricing mechanism to increase tolls for cars entering the city. It had an almost immediate impact in reducing traffic:

• February, 1 million cars reduced
• March, large increase in public transit utilization
• April, large reduction in congestion
• Manhattan foot traffic finally tops pre-pandemic times

The Federal government, always eager to increase fossil fuel consumption, has revoked the needed authorizations and demanded that NYC end the congestion pricing mechanism. The two parties will present their arguments in court in October 2025.

I hope congestion pricing stays. The city is better for having it in place.

National Climate Assessment team disbanded

By Ed Hawkins, climate scientist.
CarlinMack created this version.

Three weeks ago contracts for the National Climate Assessment were defunded and work stopped.

Today the 400 people working on it were disbanded.

Production of the report is funded and mandated by law. Presumably in 2028, AI will write something.

Finding a Role in Climate

Climate Week is drawing to an end, not yet done but one can see the close approaching.

I have spent a bit over a year now on my own, doing some consulting work while looking for longer-term opportunities but also taking downtime away from the industry. I’m very motivated to work on climate, building on earlier efforts:

• two years as a Senior Fellow at Project Drawdown
• several years coaching climate community members starting their careers
• Cohort 5 of the ClimateBase Fellowship
• all of that coming after several decades in the Tech industry, at three startups (Dominet Systems, ConSentry Networks, Tailscale Inc) and two large companies (Sun Microsystems, Google). I held roles from ASIC designer to software manager to VP of Engineering.

I’m starting to focus again on finding the right long term opportunity, not just consulting. What I’d request of those whom I’ve worked with or had the pleasure to meet along the way is introductions at the right stage, for roles with:

• a focus on climate as the primary mission. Energy is the best match for my skillset, but I believe that land use and agricultural tech need more effort and I have relevant experience with satellite imagery.
• a position which is substantially leadership, from Director at a large company to Founder / Founding Engineer or VP at an earlier stage. I can help hire, evolve organizations, and build a product.
• a technical component which is not zero. Managers should manage, but I believe managers who completely lose touch with the reality of the engineering work become less effective as leaders. I would seek an opportunity where there would be suitable opportunities to contribute technically, and believe it is important that the team see those contributions.
• an organization with a European connection. We enjoy Europe, have travelled in Germany several times, and have substantial family connections there.

These sorts of opportunities are mostly not posted publicly. I have responded to a few public postings over the past year, that is not an effective way to proceed. I’d ask for warm introductions you may be aware of, early in the process, perhaps when founders are talking about a new venture or considering a new project which needs leadership.

Thank you so much for any connections you can provide.

SF Climate Week Opening Keynote

As I did last year, I took the train to get to SF Climate Week. In this area that means taking Caltrain up the Peninsula before switching to the Bay Area Rapid Transit (BART) to the Embarcadero, then walking to Climate Week at the Exploratorium.

Both of those train systems have been substantially improved since last year:

• Caltrain completed a years-long electrification project, replacing all of the diesel trains.
• BART finished deployment of a new generation of cars, retiring all of the 25 year old rolling stock.

From this one might infer a renaissance of mass transit deployment in urban areas... but one would be wrong. Indeed, in nearly every area of climate action where the Inflation Reduction Act had spurred progress, the new administration of the last three months has attempted to roll it all back.

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Former Vice President Al Gore presented the opening keynote speech, fiery and powerful.

SF Climate Week 2025

This is SF Climate Week! The opening keynote with former Vice President Al Gore, long-time Speaker of the House Nancy Pelosi, & SF Mayor Daniel Lurie is this afternoon at The Exploratorium in San Francisco.

I'll be in SF this week as a volunteer helping keep things running, hope to see you there.

Coal Mining Policies

New coal policies are invariably announced in front of a group of workers wearing hard hats with lights affixed, and often in Pennsylvania for good measure. One might assume the mining profession is a huge economic force and under constant threat which must be fended off to preserve families and livelihoods.

As a profession, coal mining employs about 40,000 people in the US.

Source: FRED (Federal Reserve Economic Data).

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Construction Management requires similar levels of education and experience and according to employment statistics enjoys a similar pay scale. There are 10x to 20x more Contruction Managers in the US.

Source: FRED (Federal Reserve Economic Data).

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Coal policies are not driven by concern for workers. Coal policies are driven by concern for fossil fuel profits, which have only been made possible by externalizing the cost of the damage to human health and acceleration of global warming.

Electrified USPS Fleet

In its initial proposal for a refreshed fleet of delivery trucks in 2022, the US Postal Service and its contractor Oshkosh Defense proposal listed a combined vehicle + cargo weight of 8501 pounds. This is a remarkably specific number, exactly one pound heavier than emissions rules would constrain. Were the vehicle 1 pound lighter it would be required to be considerably cleaner — and likely electric, to meet those requirements.

With more effort, and additional $3 billion in funding from the Biden administration, by the following year this proposal was revised and proposed that most of the fleet be electric. A gasoline version would be used for long routes in rural areas without sufficient charging infrastructure. Initial electric vehicles were delivered in September of 2024, apparently to excellent reviews by postal workers using them.

Oshkosh has delivered only 100 electric trucks thus far, production was expected to ramp up from the initial deliveries a few months ago. The Oshkosh Defense CEO now says they'd be happy deliver the rest of the order as solely gasoline vehicles. It is difficult to see this in any positive way.

A Tale of Two Crises: Y2K and O₃

"Y2K," or 1/1/2000, was 25 years ago today. Dire predictions of how bad the Y2K Bug might be, with the failure of computing systems leading to widespread disruption, did not manifest. NPR chose what has become the dominant framing, a cynical take that Y2K was overblown and a delusional over-reaction. A nothingburger.

It is easy to see why one might believe this. Since 1/1/2000 we have lived through a seemingly neverending series of grift bubbles: the dot-com bust, subprime mortgages, cryptocurrencies, etc. It is easy to assume that Y2K was surely similar, a cynical hype cycle enabling some kind of profiteering.

 

Y2K Spending

To be clear: money was spent. Y2K remediation wasn't just some developers combing through COBOL, as is often depicted. It was more cost effective to simply replace a lot of computing systems from the 1970s and 1980s with something more modern.

Development of the modern Internet was accelerated by Y2K spending. The new systems were usually Windows Server or some form of Unix, with TCP/IP and robust networking built in. Businesses in many industries, their upgrade cycle moved up to meet Y2K demands, could make their service available on the Internet years earlier than they otherwise would have. I think we can even see it in the oft-cited productivity gains of the late 1990s.

Yet all of that effort and all of that spending wasn't in service to a fake grift. It worked. We fixed it. We actually fixed it. It is perhaps difficult to comprehend from our vantage point in 2025, but we faced a large problem and we solved it with a correspondingly large effort.

 

The Ozone Hole

We will digress for a moment to a different topic which might not seem related, but is: the Ozone Hole of the 1970s and 1980s. It is another formerly big problem which seems to have gone away — not entirely solved as the hole is still there, but the ozone layer is recovering. A common reaction is to question whether it was overhyped.

A lot of people put in a lot of effort for a lot of years replacing chemicals which caused most of the damage to the ozone. Money and political capital were spent: every nation on Earth ratified the Montreal Protocol mandating the phasing out of CFC manufacture.

It worked. We fixed it.

 

Why Not Now

The important discussion is not whether large challenges of the past were somehow not large challenges. The important discussion is why we have been unable to rise to similar challenges now.

• Climate change is everywhere but we're still debating whether it will be so bad and equivocating on what to do.
• Covid-19 should have led to HVAC retrofits to improve indoor air quality but it instead empowered antivaxers to rip people's masks off.

Within living memory we have risen to challenges requiring the whole world to cooperate, a feat which seems impossible now.

1. Then, the forces uniting us had the most effective means of coordination and of broadcasting their message: the UN and governmental coordination, and a mass media which created a shared reality.
2. Today, the forces dividing us have the most effective means of coordination and broadcasting their message: online social media and an entirely separate infosphere.

Wind Turbines and Bird Deaths

The practice of painting one blade of a wind turbine in order to increase its visibility to birds is becoming commonplace. Avian brains are not wired to detect such enormous structures as a threat, but increasing the contrast and making the movement more visible helps them see it as something dangerous to be avoided.

To be clear: this is a good thing. Harming birds, even unintentionally and without malice, is bad and taking steps to avoid it is good.

But this is another example of bad faith attacks, launched carelessly and repeated endlessly, turning into a multi-year effort by the clean energy industry to respond to. The number of birds involved was tiny, less than 0.02% of bird deaths. A study in South Africa found 848 birds killed, over the course of four years, across 20 wind energy sites. This is not a large number.

The next set of allegations about wind power are harder to refute because they are completely fabricated: that wind turbines cause cancer, or that offshore turbines kill whales.

The people making this stuff up do not want to challenge clean energy to be better. They are not interested in seeing improvement to address whatever harm they cite. They are only interested in deterring the deployment of clean energy because money from fossil fuels funds their movement. It is all in bad faith, and the disproportionate cost falls on clean energy to address.

Caltrain Electrification

Caltrain is a large publicly owned train service in California. For the past few years Caltrain has been installing electrical lines above the tracks running up the San Francisco peninsula. Train electrification was proposed thirty years ago, began work seven years ago and completed in September 2024 with the retirement of diesel and replacement by electric engines.

The electric train engines have considerably better acceleration, important given the number of stops along the peninsula, and can complete the journey from San Jose to San Francisco in 30% less time than the diesel engines could. This allows trains to be scheduled more frequently.

 

Induced Demand

Studies have previously shown that service frequency has a significant impact on ridership, and indeed, Caltrain ridership is up 54%. On weekends it is up even more, by more than double.

We talk about the Braess paradox, where adding a lane to a busy roadway will further increase traffic and result in more congestion not less. Building massive highways doesn't resolve traffic congestion for car travel.

Yet increased ridership does not trigger the Braess paradox in train networks. Inherent in the paradox is that moving entities choose their own route, and will optimize for their individual outcome even at the expense of the whole. The trains are not making individual optimization choices, they just run faster.

 

Electrified Trains are Better Neighbors

As a family we enjoy a restaurant right next to the San Carlos Caltrain station, one with outdoor seating. The most recent trip there was a revelation: the electric train is quiet while getting underway, and with no diesel fumes. Electric trains fit into the cityscape more cleanly, quietly whisking passengers on their way.

 

Emergency vs Loadshifting Batteries

Our house has 8 kilowatts of solar generation and 27 kilowatt-hours of battery storage, and is on a time-of-day electricity plan where power is cheaper in the early part of the day and more expensive from 3pm until midnight. We use 70% of the battery capacity to power the house during the peak hours each day, reserving 30% in case of outage.

This does work, but one battery is filling two roles with requirements at least somewhat in conflict.

• For load shifting we would prefer to use more of the battery to reduce our energy bill.
• If there is a power outage, we'd prefer to have more of the battery held in reserve than 30%.

Yet the batteries wired in to the house are not the only substantial energy storage on site. We also have an electric vehicle, with as much battery capacity as the house. A more modern EV than ours would have even more battery capacity.

 

Vehicle to Grid

That the substantial battery power in EVs could be useful in grid emergencies has long been recognized. Vehicle-to-Grid (V2G) is an idea to make the charging port of the EV bidirectional: charging the EV from the grid as normal, but also able to supply to the grid by draining the EV. In very large numbers, EVs could provide enough power to stabilize grid operation while still having enough power to be used for transportation.

V2G has been slow to catch on, owing mainly to the number of parties involved. Because it entails connecting a new generation source to the grid, it must follow similar processes and permits as a rooftop solar installation. The timeline of a solar install is long: it can be months with roofers / installers / electricians in several waves, and having time enough to apply for the needed permits and interconnection agreement.

Yet when people buy an EV they need a way to charge it almost immediately. Waiting to install an EV charger isn't realistic, so it will be installed to only draw from the grid not supply back to the grid. Designing V2G capabilities into an EV charger in hopes the homeowner will followup with additional permitting? Most consumers wouldn't ever do so.

 

Vehicle to Grid Vehicle to LOAD

Vehicle-to-Load (V2L) is an idea with fewer stakeholders involved: allow the vehicle to supply power to locally connected loads, most commonly by having electrical outlets and an inverter built into the car. This is useful in many situations, like an EV at a job site powering tools or while camping or picnicking.

V2L also allows the EV's stored power to be used at home during emergencies, albeit somewhat awkwardly. It doesn't power the whole house, it can power appliances which are unplugged from the house and plugged into an extension cord from the vehicle. Keeping cell phones charged, running medical equipment, or powering freezers full of stored food is quite feasible. Running central air conditioning is not.

This concept works well for emergencies in that it can power essential needs from a very large battery, especially because the battery is mobile and could go somewhere to charge itself if needed. Natural disasters in the last several years have demonstrated this, notably Hurricane Helene in the US Southeast just last week. EVs are helping supply power in damaged areas.

California, my home state, has a large enough market for automobiles that it has often been able to influence the auto industry throughout the US such as via fuel efficiency standards. A law being considered would allow the state to mandate Vehicle-to-Load capabilties for vehicles sold as of some future date.

 

Transfer switch

We'd very much want our next EV to have this capability. Our use of the batteries built into the home would change to entirely load shifting to further reduce our demand on the grid during peak hours. During a power outage of appreciable length, we'd rely on the much larger batteries in the vehicle to keep food frozen and cell phones charged.

For this to work we'd need to plug appliances into an extension cord from the vehicle, and some of them are hard-wired into the house. The traditional way to handle this is a transfer switch, intended for a generator. This is expensive, and difficult to retrofit. There needs to be an easier way.

Powerwalls and Time Based Controls

We are on a Time-of-Day electricity plan, the PG&E EV2 plan. Our cost for electricity is:

		Summer	Winter
Off-Peak	12am - 3pm	$0.31/kWh	$0.31/kWh
Mid-Peak	3pm - 4pm	$0.51/kWh	$0.48/kWh
Peak	4pm - 9pm	$0.62/kWh	$0.49/kWh
Mid-Peak	9pm - 12am	$0.51/kWh	$0.48/kWh

We are incentivized to keep the power-hungry activities like charging the electric vehicle to the daylight hours where solar is plentiful or overnight where demand is low. Unfortunately however, there are several confounding factors to our energy use which make things more complicated.

1. The house is on a hill, the crest of which blocks direct sunlight for longer and longer periods each winter day.
2. We have two Powerwalls, able to store 27 kWh to supply the house at other times.
3. BUT, when we installed the powerwalls in 2019 we claimed the Residential Clean Energy tax credit which requires the batteries be charged using only solar power for five years.

Combining all of these things, we ended up with an unfortunate confluence in the winter months when the hill allows only a few hours of direct sunlight: there is not enough excess solar to charge the batteries while also powering the house.

We would head into the higher priced times of day with little ability to time shift stored solar production. The batteries were never able to charge. Our power bills rose substantially, calling into question why we paid for this stuff in the first place.

The Tesla app has a "Time Based Control" mode, where it takes the time of day and rate plan into account. However its main focus is in exporting solar production during high value hours by running the home from battery. Lacking sufficient production to charge the battery, this resulted in poor outcomes with Time Based Control. I didn't look at it again for the next few years.

 

Hacking Around It

Instead we've come up with techniques to get things working acceptably:

1. On winter mornings set the Powerwall to reserve 100% of its capacity for power outages. All solar production during the day charges the batteries, trying to reach 100%. The home's needs are met from the grid during off-peak hours.
2. When peak hours start, change the Powerwall to 30%. It then discharges to power the home, allowing the evening load to be partially met using stored solar power.
3. Do this every day. Change the Powerwall setting in morning and afternoon, every day, all winter.

I of course wrote software to automate this, but Tesla has only recently decided to offer an actual API to control Powerwalls. For the first few years I was instead using authentication mechanisms and APIs which a community on GitHub would reverse engineer, and which Tesla kept deliberately breaking. I had to watch for errors from my software or, maddeningly, when it would run without error but Tesla ignored its commands.

 

Changing the Game

At the beginning of this month, our five years was finally reached. I set the Powerwall to be able to charge itself using grid power. This didn't immediately change much behavior, until I toggled it to Time Based Control again.

Now, suddenly, things are much improved. At 3pm every day the Powerwall begins supplying the house energy demand, and all remaining solar production is sent to the grid. At midnight when rates drop, the Powerwall charges itself to 100% using grid power, to be ready for the next day.

This is already better than the system I had cobbled together:

• There were many days when the total solar production could not fully charge the batteries. Now, no matter what, the batteries are 100% charged every day.
• We are on the Net Energy Metering plan from 2019. Sending solar to the grid offsets our use at other times, so long as the house can be powered from battery.

 

Futures

I do want to change the current behavior in one way: instead of charging from the grid overnight, I'd prefer the Powerwall try to charge from excess solar. In summer it will usually be able to do so, and in winter it can try and then start charging itself mid-morning from the grid if it isn't going to make it to full. I'm looking into the Fleet API which Tesla published this year for what might be possible.

However, fundamentally, this stuff needs to be easier for the homeowner. I've been writing custom software and manually intervening for years, just to get a decent result out of it. I should not need to do that, after having paid so much for the system install.

One small provision in the Inflation Reduction Act was to remove the five year solar charging mandate for batteries installed after its passage in 2023; the goal is to incentivize more batteries on the grid. With freedom to charge the battery, it should be able to figure out how and when to charge itself. The behavior of the system over time should inform future operation, deciding when to charge from the grid and when to trust that solar power will provide. Next-day solar forecasts can inform this decisionmaking.

Surplus Energy Response

The phrase "too cheap to meter" entered the energy discourse in the 20th century, referring to the potential of nuclear power. Though originally coined to refer to fusion power, the label instead became associated with all nuclear energy. Seventy years later fusion is not here yet, and fission power has been a solid source of baseload power but could never be described as cheap.

The idea of energy too cheap to meter is a compelling one, we just had to wait for an entirely different technology to deliver it: solar photovoltaic. Panels installed on residences and commercial buildings are typically installed "behind the meter," where it directly supplies the energy demand of the building. The proof that solar power is too cheap to meter is that is not, in fact, metered.

Solar deployment has grown incredibly rapidly, faster than the distribution grid would be ready to accept it all. Deployment behind the meter has been essential because the grid in front of the meter hasn't been able to deploy new capacity so rapidly, and solar deployment continues to accelerate. A post by Ben James argues that solar energy can be deployed so inexpensively that using it completely off the grid, for economic activities which can be economical with free energy so long as it can handle being run intermittently only when the sun is shining, is compelling.

• hydrogen production, via electrolysis of water
• fertilizer production, producing ammonia via air capture and energy
• kerosene production, also via air capture
• ... and other chemical processes made possible by prolific free energy

 

Surplus Energy Response

The electric grid has a notion of Demand Response, when there is heavy demand which stresses available generation — for example, by air conditioning on a hot afternoon. We have reached the point where we also have the opposite situation: we need a surplus response. Many builings now produce substantial excess behind-the-meter power during the day, so much so that the grid cannot absorb it all. We need our buildings to become smarter about putting the excess energy to useful work:

• pre-heat or pre-cool HVAC, somewhat overshooting the temperature setpoint while energy is free
• store hotter water, with a smart water system to mix scalding with cold to get the desired water temperature
• charge electric vehicles for free, with knowledge of when the vehicle is likely to be needed
• charge up batteries in appliances throughout the building, allowing high peak load appliances to be installed in buildings not originally built for them

Yet we can take it even further. Limitless free energy, albeit at limited time ranges within a day, allows us to make choices we would never have otherwise considered.

• heat a pool or hot-tub to be ready for impromptu human use at any time during summer months
• run heat pumps in a sunroom, open to fresh air yet maintained at a comfortable temperature
• indoor urban hydroponics, pre-engineered gardens which are never too hot nor cold and provide generous fresh produce

In building enthusiasm for the energy transition, providing services which seem impossibly luxurious yet are provided entirely by surplus energy would be a compelling outcome.

EVs Are More Than Their Range

We have a 2016 Kia Soul EV. It uses a 27kWh battery pack, quite small compared to other electric vehicles which commonly have 50+ kilowatt hours of capacity. We've used the Kia primarily as a city car on local roads with only the occasional highway trip. As a city car it has been fantastic, small and easy to park yet large enough to handle our typical trips like groceries and taking kids to school.

When new the car would get 80+ miles in city driving on a full charge. Its battery slowly degraded each year until a few months ago when it began dropping quite rapidly. OBD diagnostics can read the state of each individual cell in the battery pack, enough of the cells had failed for it to be replaced under warranty.

This post is not about the battery replacement process, though we are quite happy with Kia and the warranty support.

This post is about how useful we find an electric vehicle even with fairly limited range, and how little difference it made when its range suddenly increased. The first time we charged the car with its new battery pack its range estimate read 101 miles. Honestly I didn't even know it could display three digits.

We charge the car using solar production in excess of what the house is using. Where before we would charge the vehicle every day, we're now charging it mostly on weekends. It has triple the battery capacity but 5x above the reserve level we like to keep. It can go all week on our usual errands.

It seems somewhat strange to me but our use of the vehicle has not really changed with all this extra range. The new energy ecosystem was already compelling for us:

• Solar panels on the roof produce substantial extra energy during the day.
• Not having to pay for gasoline or oil changes further improves the economics.
• Most trips are short. On any given day we drive just a few miles.

When we talk about the fossil energy system we point out how damaging its emissions have been, and how the cost of that damage is completely externalized from production. All of that is true. Another aspect of the fossil energy system is how ruthlessly it pulls profits back up the supply chain, resulting in enormous profits at the top and almost nothing to the rest of the ecosystem. Gas stations make their profit from snacks, carwashes and oil changes, the gasoline sale merely brings people in while the supplier takes all of the profit. Methane pricing encourages spikes to ruinous prices for electricity distribution operators.

Distributed energy production and distributed ownership of energy production also results in more of the benefits being distributed. Our little electric car is part of a larger whole where one can capture and use the energy from the Sun without some entity in the middle siphoning off the benefits of doing so.

Update: a few weeks after publishing this, both of us parents had conflicting appointments and I had to drive the EV further than its previous battery could have managed. It was glorious. More range is certainly better. Still, our use of the car is mostly just short trips around town.

Heat Pump HVAC firms

We had a Mitsubishi mini-split heat pump system installed in 2019, to replace a pair of gas furnaces. We love the system, but finding an installer was more difficult than I had expected. Almost every HVAC installer wanted to install new gas furnaces and be done with it, even those which mentioned heat pumps on their site. They might have eventually been cajoled into installing what we wanted, but that wasn't the kind of vendor we wanted.

We ultimately found Alternative HVAC Solutions, which specializes in heat pumps and leads with them as the solution they propose. They did a fine job and I do recommend them for anyone looking for an installer on the San Francisco peninsula.

However this morning I had to SQUEEEE with excitement at seeing another firm proudly leading with heat pumps as their preferred solution: Electric Air. I cannot speak from personal experience about their service, it is just nice to see how far we have come.

I wrote about our heat pump installation in 2019.

The Decapitated Duck Curve

California invested heavily in solar and wind starting more than a decade ago. So far in 2024 renewable sources have met 100% of the state's energy needs for at least part of the day since early March, and continuing through the time of this writing in August 2024.

Solar growth in particular has been robust enough that it started to perturb the operation of the grid nearly a decade ago, the infamous duck curve where demand seemingly drops in the middle of the day:

A great deal of solar capacity in California has been installed by property owners on their rooftops, both residential and commercial, fed directly into the electrical panel of a building. This supplies energy to the building without the grid seeing anything at all. From the perspective of the power grid the demand for electricity simply drops during summer afternoons, more every year as more solar panels are installed on more rooftops.

However California is experiencing something new in 2024: the duck no longer has a head. Or at least, the use of methane to supply power to the head of the duck has abruptly fallen.

the decapitated duck curve

The dip in the middle of the day is still there, a reduction in demand due to rooftop solar generation. However where methane power generation used to spring back up in the late afternoon as solar production falls off, in 2024 the demand only rises partway back above its low point. The head of the duck is no longer there.

The difference is that the capacity of battery storage on the grid has risen rapidly and passed a tipping point. Much of the late afternoon demand can now be supplied from solar sources, shifted in time using batteries.

California's tax incentives now aim for the installation of more battery capacity. Property owners are free to install solar panels on their rooftops to meet their own demand, but the state doesn't need more solar generation and panel prices have dropped well below the prices where tax incentives were essential. Adding more battery capacity will allow the state to continue to carve the duck, by timeshifting more of the prodigious solar power generation to be ready after the sun sets.

Like solar on the roof, batteries installed in a building appear to the grid as though demand is lower. In reality the demand for electricity is not lower, it is simply being satisfied by batteries before the electric meter sees it. Where we've already seen a reduction in gas generation, we'll begin to see a flattening of the demand curve as the buildings on the grid gradually power themselves for even more hours per day.

Rivian Updates R1 Models

Rivian’s revised R1 vehicles look really nice. They focussed strongly on production cost, to make each vehicle sale more profitable. Their recently announced R2 and R3 vehicles, smaller and with a lower MSRP, would be their way to try to reach more customers.

Passenger vehicles are not a part of the climate space that I worry about as much as other segments. EVs have several inherent advantages:

• Far fewer moving parts. Over the long term, EVs are more reliable and will be cheaper to maintain.
• ICE engines deliver about 20% of their total energy to moving the vehicle, EVs are >50%. Moving the entire energy requirements for passenger vehicles onto the electric grid would result in using substantially less total energy.

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We need more climate change work to reach this level of clear superiority over legacy methods.

• Solar energy production got there first, all of capitalism's incentives are now driving toward more solar installation.
• Concrete and steel production show exciting progress, that the resulting materials are actually superior to what came before in their durability and control over material properties.

More. We need more.

Heat Pump Water Heaters and Residential Engineering Departments

A few weeks ago the US Department of Energy finalized efficiency requirements for residential electric tank water heaters. The efficiency requirement was last updated in 2010 and is supposed to be revisited every 6 years, but was not done during the 2016-2020 Presidential term. The new requirement will take effect in 2029, and should result in substantially more effort to make heat pumps the default choice for electric homes. The regulation does not mandate heat pumps specifically but most manufacturers will decide that heat pumps, a proven technology, are the most sensible way to increase the efficiency of their product line.

The push by manufacturers is important because water heaters are frequently replaced with little time for the end user to investigate alternatives because the old unit has already failed. We replaced the water heater in our home in 2021, moving from a gas appliance to electric. We had enough time to find an installer in our area familiar with heat pump installation — emeraldECO, in our case — but not everyone will have that amount of time to make a decision.

Having manufacturers make heat pump water heaters be the default means that contractors will need to train their crews to be ready to install heat pump water heaters, or risk losing business. They have to be prepared to explain the technology to their customers, and to help navigate available in incentives and rebates for the devices. It is a way to incentivize the entire supply chain from manufacturer to distributor to contractor to end-user.

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Revisiting an earlier topic: a more sophisticated product installed in the residence brings more complexity in operating the infrastructure. Our heat pump water heater has a Wi-fi connection. It can notify us of faults... and has. It has signaled a blocked overflow pipe as a problem, but following up showed no blockage and no sign of a problem. The design of infrastructure for residential use has to take into account that the property owner won't be knowledgeable about its operation. There won't be an engineering department.

Residences as Utility Infrastructure

The universal first troubleshooting step is to reboot. No matter what the product is, no matter what the problem is, try turning it off and back on &emdash; which is how I found myself figuring out how to reboot a solar inverter. It turns out to be difficult to power cycle something which makes its own power.

When we added solar panels to the roof in 2019 we chose a SolarEdge inverter with an integrated vehicle charger, expecting to never acquire another gasoline car. We have been happily using the SolarEdge inverter to charge the EV we subsequently acquired.

Happily charging until Saturday, that is. I boggled plugging in the car, quickly pulling the plug out and back in without fully intending to. The inverter beeped and the car's indicator lit when first plugged in, then turned off and didn't come on again. There it sat, neither charging nor disengaging no matter what I did. Left a few hours, it just sat there not charging. Plugging it in again the next morning did not change anything.

So: time to reboot the inverter.

Getting an inverter to fully reboot requires cutting power from every source that sneaky thing might use:

1. Turn the switch to disconnect from the photovoltaics.
2. Turn off the breaker where the inverter connects to the house electrical panel.
3. Pull the shutoff switch to disconnect from the grid completely. This would have powered off the whole house were there no batteries.
4. Wait for capacitance in the inverter to drain and all of its LEDs to turn off, then another 60 seconds.

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Commercial buildings have long been responsible for substantial utility infrastructure, from boilers to electrical transformers to, sometimes, subway connections and underground steam tunnels. Residences have typically hosted much less infrastructure, and the equipment has been gradually refined so as to be simple for the homeowner. Ground fault breakers, electric starters for pilot lights, and so on have all been developed to minimize the need for a residence to have to deal with odd failures or dangerous conditions.

The clean energy transition is moving more infrastructure into residences which might once have been exclusively the domain of a service provider. Very few homes have a private gasoline station, but many will have private chargers. Very few homes have generators supplying their electricity, but many will have solar and virtual power plants using residential batteries in unison are already here.

The design of infrastructure for residential use has to take into account that the property owner won't be knowledgeable about its operation. There won't be an engineering department, there won't be anyone paying attention to it. I have on the whole been happy with the inverter and the Powerwell it connects to, but there is more to be done to handle odd cases like this.