So the last of these, A.I., recently has led to a lot of reading and arguments with my friends. I realize how much I rely on my calculator, my phone (actually mini-PC), and all the other modern electronic helpers we take for granted now. I am disappointed in how much less I process between my ears, instead relying on my fingers to do so many calculations and retrievals.

One of my best friends insists I have a bad attitude about this. He is using A.I. engines to improve his firm’s service products. He subscribes to my Electrify post and decided to ask his engine (Claude, no last name) what was wrong with my post.

Well I will relieve you of having to read the specific criticisms of my research and writing, and will simply offer you Claude’s version of that same 21st Century Grid Challenges post for fun.

21st Century Grid Challenges: Beyond Simple Electrification

Gerald Glaser as rewritten by Claude
Nov 16

In my previous post, I explored how the electric grid functions and why its operation is remarkable. Now I want to examine why yesterday’s solutions won’t solve tomorrow’s distribution challenges—and propose a more nuanced path forward.

The Scale of Change

From 1900 to 2000, world population grew 3.8-fold while energy use grew 8.5-fold. In the United States specifically, energy consumption increased from 2,700 tWh to 28,633 tWh—a tenfold increase—while population only tripled. This disproportionate growth in energy intensity has defined modern life.

The transformation wasn’t just in quantity but in form. In 1900, primary energy sources were coal and wood, burned directly for heat. By 2000, our energy mix included nuclear (8%), coal, natural gas, petroleum (40%), and renewables (7%, primarily biomass and hydro). But this shift in sources masks a more fundamental transformation: the conversion from primary heat energy to electricity.

The Efficiency Paradox

Throughout the 20th century, when energy primarily meant burning fuel for heat, direct combustion made sense. But as we needed energy for transportation, lighting, and complex machinery, electricity became essential despite its conversion losses.

Converting fossil fuels to electricity wastes substantial energy at each transformation step: chemical bonds to heat, heat to mechanical motion, mechanical to electrical. According to Lawrence Livermore National Lab’s 2023 data, of 93.6 quads of primary energy harvested in the U.S., 61.5 quads (66%) were rejected as waste heat before doing any useful work.

When electricity was a luxury, this inefficiency was tolerable. Today, electricity consumes 22% of primary energy, up from 0.1% a century ago. With building electrification, electric vehicles, and new industrial processes like electric steel production, this percentage will continue rising sharply.

What the Numbers Actually Tell Us

We’ve achieved remarkable efficiency gains: buildings are better insulated, LED lighting is 90% efficient versus 5% for incandescent bulbs, hybrid cars achieve 50 mpg, and aircraft have dramatically improved fuel economy in just twenty years.

Yet total energy consumption—and especially electricity demand—continues growing. This isn’t a failure of efficiency; it’s the Jevons paradox in action: as energy use becomes more efficient and cheaper, we find more applications for it.

Here’s where the scale becomes clear. My household provides one data point: after insulating our home, reducing appliance loads, and converting to all-electric systems including two EVs, our total energy consumption dropped 62%. But our electricity consumption nearly tripled. If this pattern holds broadly—and early data suggests similar trends—the distribution grid faces an unprecedented challenge.

To put this in context: PG&E serves approximately 16 million people. If even a quarter of households follow similar electrification patterns over the next decade, the distribution system would need to handle roughly 50-75% more peak capacity in many neighborhoods. The current grid wasn’t designed for this.

The Supply Question: Largely Solved

Several years ago, I attended a board meeting where our local electric utility presented load forecasts to the California Public Utilities Commission. Their model projected minimal demand growth, assuming efficiency gains would offset new electric applications. That assumption is being rapidly reconsidered.

But can we actually generate enough clean electricity?

The answer appears to be yes. In 2024, the EIA reported that new generating capacity broke down as: 58% solar, 13% wind, with nuclear beginning to ramp up again, while fossil fuel plants represented only 4% of additions. In my region, advanced geothermal facilities are being developed that can be built almost anywhere by tapping deep earth heat.

Total new capacity in 2024 was projected at 62.8 GW—55% more than the 40.4 GW added in 2023. For context, total U.S. generating capacity is approximately 1,200 GW, so we’re adding roughly 5% annually, with renewables dominating. At current growth rates, generation capacity should keep pace with electrification, though regional bottlenecks and timing mismatches will create challenges.

The generation problem has technical and economic solutions. The distribution problem is more complex.

The Cost Question: More Nuanced Than It Appears

A builder I spoke with recently questioned whether the grid can handle growing electric demand. His concern: “Where is all that energy coming from? It’s really expensive compared to existing fossil fuel options.”

Let’s examine this carefully.

California has the second-highest residential electricity rates in the nation at 30.72¢/kWh (after Hawaii), compared to North Dakota’s 7.42¢/kWh and a national average of 15.59¢/kWh. This disparity requires explanation.

Natural gas prices are highly volatile: $9.33/MMBTU in 2022, $1.63/MMBTU in 2024, currently $4.31/MMBTU. PG&E charges $6.70/MMBTU for the gas itself, plus $22.20/MMBTU for delivery. This means delivery costs represent 77% of what consumers pay.

Even if gas prices double, consumers only see a 23% bill increase because delivery dominates the cost structure.

Electricity pricing is more complex, with Time-of-Use schedules, seasonal variations, and zone-based rates. During winter peak periods, 67% of electricity cost is delivery infrastructure; in summer it drops below 50%. California’s high rates stem largely from aging infrastructure and wildfire damage liability—costs that should decrease as utilities underground lines and improve safety systems. PG&E has already reduced residential rates in the past year while promising further reductions.

However, this cost comparison misses critical factors:

Equipment efficiency matters. A heat pump with a coefficient of performance of 3.0 delivers three units of heat per unit of electricity consumed. Even at California’s high rates (30¢/kWh), that’s effectively 10¢ per kWh-equivalent of heat. Natural gas at PG&E’s total delivered price of $28.90/MMBTU, burned in a 95% efficient furnace, costs roughly 10¢ per kWh-equivalent. The economics are already comparable in high-cost electricity markets, and favor heat pumps in most other states.

Total cost of ownership varies dramatically. Installing residential solar and batteries requires $20,000-$40,000 upfront. Not everyone can afford this, and renters, apartment dwellers, and those with poor solar exposure have no access to these solutions. Natural gas infrastructure already exists in many homes.

Long-term price trajectories are uncertain. I claim electricity will become cheaper relative to gas, but this assumes continued renewable deployment, stable policy support, and resolution of grid integration challenges. Gas prices could remain low if fracking continues, or spike if exports increase or regulations tighten. Making 25-year predictions about either fuel’s relative cost is speculative.

My fundamental position: over the 15-25 year lifespan of HVAC equipment and appliances being installed today, electricity will likely be cost-competitive or cheaper than fossil alternatives in most markets. But this isn’t guaranteed—it depends on policy, technology learning curves, and infrastructure investment.

The Question Everyone Should Be Asking

The real challenge isn’t energy generation or even long-term costs. It’s the distribution grid—that final mile from substation to home.

As I explained in my previous post, peak demand determines grid design: conductor sizing, transformer capacity, and branch circuit extent. If households triple their electricity consumption while also changing the nature of peak demand—EVs charging for hours instead of air conditioners spiking for minutes—the distribution system becomes a bottleneck.

Utilities face three options:

1. Massive infrastructure replacement - Upgrade transformers, conductors, and substations across entire service territories. Cost: hundreds of billions nationally. Timeline: decades. This is economically prohibitive.

2. Managed demand - Smart thermostats, dynamic pricing, vehicle-to-grid technology, and direct load control can flatten peaks. This helps but requires coordination, customer acceptance, and sophisticated control systems. It’s part of the solution but not sufficient alone.

3. Distributed generation and storage - Rooftop solar and home batteries can meet local demand, reducing distribution requirements. This is promising but excludes many customers and requires new regulatory frameworks for grid integration.

The realistic path forward combines all three: strategic infrastructure upgrades where needed, aggressive demand management, and distributed resources where feasible.

But here’s what’s missing from most discussions: who pays, and how do we ensure equity?

Wealthy homeowners can install solar and batteries, insulating themselves from high rates and grid constraints. Renters and apartment dwellers cannot. If utilities raise rates to fund infrastructure upgrades, they disproportionately burden those who can’t invest in self-generation. If we rely too heavily on distributed resources, we create a two-tier system.

What Comes Next

We cannot produce or store natural gas at home. We can collect solar energy and store it in batteries. This asymmetry suggests a path forward that utilities and regulators are still grappling with: a hybrid grid model where distribution serves as backup and balancing rather than primary supply for many customers.

In my next post, I’ll examine one approach to this transformation—how residential solar, batteries, and smart controls could reshape the distribution system while addressing both cost and equity concerns. The solution isn’t purely technical; it requires rethinking the utility business model, rate structures, and our definition of grid reliability.

The question isn’t whether we can electrify everything. We can. The question is whether we can do it affordably and equitably, without stranding those who can’t participate in the distributed energy transition.

!!OK, I fold!!

From 1900 to 2000 the world population grew 3.8 fold, while at the same time its energy use grew 8.5 fold. Considering these are worldwide statistics, and much of the world has not had the benefit of the energy use explosion, this is quite a change. From the U.S. EIA the energy change over that same period in the USA was from 2,700 tWh to a whopping 28,633 tWh while its population only grew 3 fold.

Over that same period a major transformation in the primary sources of energy occurred. Primary energy is the harvested source of the energy. For much of the beginning of the 20th century little transformation occurred from the primary energy form to a usable form. In 1900 the primary source forms were coal and wood. In the 1950s we were promised that nuclear power plants would provide us virtually free electricity. (It didn’t happen.) By the year 2000 what nuclear (8%) we had was supplemented by coal, natural gas, and with 40% being petroleum. Renewables (7%) at that time (primarily biomass and large hydro) were a relatively small portion of the energy mix. However, that is not the whole picture.

So throughout the 20th century coal, wood, natural gas, and petroleum were the predominant forms of primary energy. They were simply burned, converting their physical chemical bonds to heat.

If you are relying on the energy to heat and cook - that seems reasonable. However, as we started to use this energy to power transportation, provide light, and run modern machines, heat simply was not the most efficient form of energy to use. Electricity provided a more convenient and effective form. It seems obvious that rather than focusing on the primary source of energy, planning for the future we needed to focus on how the energy is distributed and consumed to do work.

Following our established pattern, we began converting those 20th century sources of primary energy to electricity. In most cases this was done by transitioning from chemical bonds, to heat, from that to mechanical engines, and finally to electricity. Each transformation step resulted in waste energy being released. From the Lawrence Livermore National Lab’s 2023 USA Energy Consumption diagram we see that of the 93.6 quads of primary energy sources tapped that year, 61.5 quads were rejected and never utilized to complete useful work.

When electricity was “nice to have” this was an inefficiency that could be tolerated. But today, even with us continuing to consume enormous amounts of fossil fuels for transportation and heating, electric energy has grown from consuming 0.1% of the primary energy to now consuming 22% of it. You can guess as buildings are electrified, with the introduction of electric vehicles, and even new processes for making steel; this transition is just the beginning.

So what’s the point?

We have been achieving amazing results in improving our efficiency in the use of energy. Our buildings are better insulated, lighting has moved from being 5% efficient to over 90% efficient, hybrid fueled cars are driving 50 mpg, and even aircraft and ships have made enormous improvements in efficiency in just the past 20 years. Yet our consumption of energy for all the things we want to do, and especially the intensity of electric energy use, continues to grow.

Several years ago I attended a board meeting of our local electric power provider. Each year here in California, load servicing entities (providers of electric energy and power) are required to report to the California Public Utilities Commission (CPUC) how they will ensure sufficient energy will be available for their future customer needs. At that meeting their model showed, as a result of efficiency measures, even with a growing population, that there was little growth in demand forecast in the future. Their assumption was that the savings achieved from more efficient technologies would keep up with the expansion of the number of applications that would rely on electricity as its usable energy source.

I believe that is now being rethought.

After improving our own home by insulating, reducing the appliance loads, and converting to an all-electric home, our electric energy consumption had doubled. Then we replaced our remaining car with another electric vehicle for our longer trips. At this point, as I reported in earlier posts, we had reduced our family energy use by 62%. That sounds great! But at the same time, our electric energy consumption increased close to 3 fold.

So what does this all mean?

In the past week, I met with someone in the building trade that questioned whether the grid can keep up with the growing demand for electric energy. In construction of new buildings and remodels, they are encouraged to use heat pumps and all electric appliances. His question was. “Where is all that energy coming from? It is really expensive compared to the existing [fossil fuel] options.”

I did have answers to that question and concern.

Where is all that energy coming from?

In 2024 the EIA identified of the energy proved from new production facilities some 58% were solar fields and 13% came from wind turbines. Nuclear is once again beginning to ramp while fossil fueled plants only amounted to 4% of new energy sources. In my local area new facilities are being built to tap advanced geothermal energy. These are facilities that can be basically constructed anyplace in the world and rely on the hotter temperatures found as you drill deep below the earth’s surface.

The above are just the utility scale additions to the energy portfolio. Again from the EIA, 62.8 gigawatts were projected to be added in 2024; this was 55% more additional capacity than the 40.4 GW added in 2023.

Basically, we are already starting to find ways to address the raw need to harvest energy sources that will not rely on burning materials. So the answer to the question of raw capacity seems to be being answered.

It is really expensive compared to the existing options.

This was an interesting comment and I kind of understand where it is coming from.

Electric energy costs in California are extremely high. After Hawaii, California has the second highest residential average cost at 30.72 cents/kWh. Contrast that with North Dakota at 7.42 cents/kWh and an average of states’ averages of 15.59 cents/kWh.

So how should I address this comment? Well there are two factors that say this long term will not be an issue.

The first factor is the forecast price change for the conventional alternatives to electricity. Primarily this is natural gas (methane).

I tried to find a source for projections for where natural gas prices might go over the next 25 years. I couldn’t find any. So I looked at the prices over the past 5 years and I learned how volatile natural gas prices are. In 2022, it was as high as $9.33/MMBTU (million BTU) and in 2024 it dropped to $1.63/MMBTU. Today it is at $4.31/MMBTU. But our local utility, PG&E, is charging us $6.70/MMBTU as of December 2024. Likely this up-charge is to address the basic volatility of the gas price.

But utility rates are broken down into a number of general parts; the energy, fees and taxes, and a delivery cost. Of the total cost to the consumer, our local utility also charges an additional $22.20/MMBTU to deliver the gas.

This brings up a point so often lost as we discuss utility rates. The cost of delivery of the energy most often determines the cost we pay as consumers. With natural gas this is obvious. So even if the gas rate varies by 100%, the consumer would still only see a 23% change in the cost, because the cost of the gas is such a small portion of the delivered price.

With electricity the picture is quite a bit more complicated. There are many different schedule rates; and variations even within them based on where you live. As well California utilities are required to shift their residential customers from tiered rates to Time-of-Use rates. So determining average costs is tricky.

As an example of this complication, the TOU EV-2A schedule has winter and summer rates. Each season has prices for peak, partial peak, and off-peak times. And these are adjusted based on the zone in which the building is located and whether or not the primary heating source is natural gas or electric. During the peak period in the winter, 67% of the cost of the electricity is the delivery cost, while in the summer it is less than 50%. So electric rates can be more sensitive to the energy costs than natural gas is.

I questioned why California electricity rates were so high compared to other states. In a large part it is our aging infrastructure and the cost of damages caused in wildfires triggered by the electric grid.

This was proven out in the past year as resulting from efforts to reduce the risks associated with transmitting electricity, PG&E has been able to reduce residential rates. The letter announcing this reduction included a promise to continue to focus on reducing rates.

So my fundamental response to the statement that electric energy is more expensive is, yes, for now! But looking forward through the life of the equipment being installed in the buildings, that will not be the case.

The question not asked.

I felt that there is a question that is often ignored. We are going to continue to increase the amount of electric energy we consume in our homes and workplaces. But as I suggest above, the challenge is not so much where to harvest that energy, but rather how to deliver it to the consumer (us). This brings the question of the distribution grid, that final mile to get to the consumer.

In The Maligned Grid post I explained how peaks determine the constraints that drive how the distribution grid is designed. It determines both the size of the conductors and the transformers, and I assume, also the extent of how large each branch can be. If each of us begins to triple the electric energy we consume (as my household did, even as it reduced the energy it consumes), the distribution grid will be under capacity to handle the change. As well, as described in previous posts, the definition of peak will need to be modified. Electric vehicles will hold peak levels for hours instead of for minutes.

The question not asked is ,
“How will we address the new distribution grid challenges without having to incur the cost of replacing those grid resources.”

We can’t actually produce natural gas at home. In fact, it is not even practical to store it at home. As we all know, we do have methods to collect energy (from the sun) and store it at our residences (in batteries). So we can mitigate the impact (and arbitrate the Time-of-Use rates) for our growing number of electric appliances.

The subject of the next post will focus on that mitigation. It will review one approach that could be taken transforming the grid, while allowing utilities to avoid expending substantial capital attempting to support our growing electric energy consumption.

Hopefully that post will provide an answer to The Question Not Asked.

I have been away from posting for months now. I kinda missed it, but I was diverted to other things.

Ok, that was actually written almost a year ago… and I never finished that post. 2024 was a rough year. I started to question what is important as result.

I started writing an other post last year that began with, “we are branching from the 20th century into the 21st. “

There was a major transition that occurred in the 20th century that those of us who arrived in the middle of that century might not have recognized.

One might argue that throughout pre-20th century history, major changes have occurred that impacted large populations. Several come to mind; the discovery of the wheel, the utility of fire, the number zero, the printing press, calculus, the steam engine, … They all had major impacts on large populations. But for each, they surfaced far apart in time and took a relatively long time to become pervasive.

As we leave the 20th century behind us, consider what you have seen change during your life. Not one discovery, but dozens of major discoveries, all surfacing during a single lifetime. And each of these impact virtually everyone in the world to some extent. Just consider how you communicate and how you get information ( or how I am communicating with you right now). It is not only the rate of change and the rate of change to those things that changed, but also, the extent to which it has impacted billions of people. (Cell phones that became affordable less than 30 years ago are a good example. There are 74 countries in the world with higher per capita cell phone usage than in the USA. And there are only 195 countries.).

         It IS kind of overwhelming to consider.

There are many topics that could be considered to demonstrate the extent of this revolutionary change, but I will leave those topics for another time (or someone else’s posts) and continue to focus on ENERGY.

Some background - My energy history

As I described in an earlier post, our first home solar installation was in 2006. It was modest in size by today’s standards; just 2.5kW. We did not pair it with batteries. Storage at that time both required extremely high cost and maintenance effort. So we decided that storage was not going to be part of our system.

Along with this solar, we got to leverage features of PG&E’s E9 tariff. This tariff was simple. It was our first time-of-use tariff replacing the tiered tariff that was customary at the time for most homes. It had a special (and simplistic) incentive feature. When we produced energy from our solar array, the meter would simply run backwards. And the meter was interesting. It was designed specifically for that tariff. In the summer, the day rate was 32 cents per kWh and after midnight it was just about 5 cents per kWh. The meter recorded the NET usage for each period and the meter reader came by monthly to record the various period values.

With this E9 tariff and as early EV drivers, we charged the car after midnight. We even scheduled our clothes drying to take advantage of the low nightly rates. The modest array collected energy and either supplemented our usage or sent it back to the utility. As a result, at the end of the first year, we not only reduced our electric bill - we actually didn’t have to pay anything. Though we consumed more energy than our little array produced, we were selling energy to the utility at $0.32/kWh and buying it for much less. Each August PG&E sent us a check for something like $80. They owed us!!!

I have to admit, as a business person I saw this as NOT a very sustainable business model. Here I was, the customer, getting a service from PG&E (reliable power and energy whenever I needed it), and they were paying me for the privilege of doing that! If I thought about it, it was even worse! They were now providing a brand new service to me. Because I had no batteries, they were storing my energy for me. That saved me both cost and bother.

At the time, I thought to leverage this unfairness to my advantage and attempted with some friends to launch a company (Scalablepower) to provide neighborhood energy systems where people could subscribe and own portions of offsite power solar systems. The startup never launched, but that’s when I began my journey in learning more about the grid and the power system we all enjoy.

Electricity? We get it delivered to our homes…

Contrary to many of my fellow utility customers, I have great empathy for the challenges our public utilities face.

When I began this post (a year ago) I characterized a shift from the 20th to the 21st century with a particular focus:

We moved rapidly from an energy light world into an energy heavy world.

My grandmother’s 1915 neighborhood home was initially built no electric connection. Electricity was a luxury. 30 years later it was common to have electricity to provide light and a few other conveniences. But today can you imagine your life without electricity? It powers much of our homes and even more of our businesses and factories. Without it much of our daily routine crumbles.

I have attended a number of forums where there are discussions regarding reductions in renewable energy incentives. Rapidly the group discussion degrades into complaints about how the greedy public utility is just trying to increase profits. Okay, some of that might be correct, but I think we need to recognize the challenges those utilities are facing as our electric grid transitions to address 21st century realities.

My posts thus far have focused on energy; how we use it, where it does come from, and where it should come from. But in a recent neighborhood meeting I realized that very few of us actually recognize how complicated and (quite frankly) fragile is the energy world we live in. AFter talking with my neighbors, I felt I would focus this post on the basics, as I understand them, of how that electricity reaches us.

Our local utility’s published uptime target is 99.999%. I like numbers - how much time does that say they expect that its customers might be without electricity in a year. It comes out to 5 minutes and 15 seconds. I find that quite a high performance goal.

Most of us don’t recognize it, but for utility electricity to be usable it needs satisfy a number of concurrent metrics. It needs to be at a particular frequency (here in the USA that is 60 cycle/second), with a specific voltage (your wall outlet is 120 volts), of sufficient power (we will get to that later), while coming from multiple sources (there are many power plants that feed the grid.)

Our homes receive alternating current (AC) energy. Basically it means the electricity moves back and forth instead of just in one direction. (Easy to understand how that works if you consider that you expend just as much energy running 5 miles in a straight direction versus running 5 miles back and forth in a gym.)

With my handy-dandy graphing calculator I produced this diagram of what our power/energy wave (Voltage on the vertical axis) looks like over time (the horizontal axis.) It shows what voltage change occurs in your outlet during 1/60 of a second. The electricity swings in one direction and then smoothly reverses itself.

Our electrical and electronic devices rely on this electricity to be carefully conditioned. Too small a voltage (the graph flattening out), results in brown outs and our equipment stops working. (Kinda like pulling the plug out of the wall.) Too large a voltage (where those wavy lines get taller) and our equipment can be damaged. (Think what might happen if a lightning bolt hit wires connected to your computer.)

But to be honest, it is much more complicated than that. The energy we use relies both on the voltage (I think of this as the level or speed) and the current (I think of this as the number of electrons moving) of the electricity being delivered. Most people (including me) use the water analogy. Voltage corresponds to how fast the water moves and current is how much water is moving.

We POWER our appliances. Both the current and the voltage levels determine how much power we get. There is a simple formula that describes this:

In most texts you will actually see this as:

Current is measured in Amperes, hence the “A”. And like Voltage, the current also varies over time. (Other equations use “I” to designate current.)

So imagine as Voltage swings to its maximum on the curve that Current is zero at that point. That would result in Power ending up being zero. In that case your appliance simply won’t run. So the first challenge after making sure the Voltage and Frequency are correct is to ensure the Current is synchronized with the Voltage in order to result in positive power.

The very first electric “grids” were pretty small and only had a single power plant. Once the utilities began growing, grids required multiple power plants, and utilities had another challenge. All of the plants would need to produce their power in step with each other, ensuring they were adding power to the grid at the same frequency and voltage. If they did not the resulting wave form would change and be somewhat bumpy.

But even if they did achieve the same frequency and voltage, using simple electrical circuits, they must still ensure they continue to run in phase; that is the zero voltage time and peak voltage times must be synchronized.

Here is a diagram demonstrating what happens when two plants (the red and blue lines) didn’t end up in Phase. Notice how it results in decreasing the grid voltage (green line). That green line would cause a brown-out.

So you can guess, with multiple power sources on an interconnected grid starting in 1921 and throughout the 20th century, that utilities had a complicated problem to solve. However, with complete visibility over the sources of power and delivery, it was possible to put the controls in place to ensure all the power sources feeding the grid complemented each other.

However, they still were challenged as they had virtually no control over the demand. DEMAND is us consuming the power.

The matching Demand Problem

I have to confess, that originally I never considered how the grid functions. I was thinking they produce the electricity and it is there for me to use. But I didn’t consider MY ROLE in the stability of the grid. As I turn on my appliances, I consume some of that power.

Here that water analogy starts to work again. Imagine that my power use corresponds to me pumping some water out of a river that is flowing past me. Well that means there is less water for the folks downstream. If enough of us do that at the same time, then the stream will start to lower and eventually dry up.

And that is exactly what happens on the grid!. As we use the power on the grid to run our appliances, the grid power starts to drop (brown-outs). If the utility responds by pumping more energy out, but we all suddenly stop using power… flooding… The voltage on the grid climbs above that 120V.

In fact that brings us to the next grid complication.

              AT ANY INSTANT IN TIME, THE SUPPLY ON THE GRID 
                  MUST MATCH THAT INSTANTANEOUS DEMAND   

Throughout the 20th century, pretty much the utility had complete control over the supply either through its own facilities or through the agreements they have with power providers. (In California public utilities can only own nuclear and large hydro energy plant. All other power they are required to source from 3rd parties.) So you can imagine what a challenge it is to increase or decrease power on the grid to match precisely a fluctuating demand that you have no control over.

Luckily with millions of us, statistically the hourly demand could be somewhat accurately projected. Heat waves and sudden failures in supply could still cause unexpected excursions. But the utility does a pretty good job of keeping the balance and achieving their uptime goals.

It is quite a balancing act that is supported by studying historical use patterns. But now we move from the 20th century realities to the 21st century expectations.

So let’s throw some more variables into the mix and see what happens.

Renewable energy causes problems

Perhaps you can already guess why I say Renewable energy causes problems from the hints I gave above. Utilities pretty much had control over the electricity supply and they depended on predictability of demand patterns to provide the reliable, high quality power and energy we have come to expect from them. The 21st century is going to not only introduce a change in demand intensity, but because we are introducing renewables quickly as a Distributed Resource Energy (DRE), the supply-side controls and reliability are being compromised.

The nexus of Distributed Resource Energy and Renewable Energy is the supply challenge posed in the 21st century.

With DRE, the utility no longer has control of the supply. In fact, it has little visibility of when the energy comes online or drops off. And the source of Renewable Energy, even if they were centralized, are uncontrolled. The sun shines at specific hours, but the clouds control its intensity. Weather impacts both solar and wind supply. And unlike when one power plant has an interruption, when a neighborhood suddenly is darkened by a storm front, every home’s solar system will curtail production of electricity.

What's the big deal?

So hopefully I left you with an appreciation of how challenging it is to deliver reliable, high quality electric power to us. We take it for granted, but indeed it is a technological marvel.

In this post, I describe how DRE and Renewables will force a change in the way we achieve continuing to have a stable grid. In a previous post (Electrify Everything) I covered my experience that demonstrates how peaks will shift as electric vehicles become the norm. This shift in intensity too will play a large role in determining what grid changes are necessary.

21st century solutions for 21st century challenges

We assume the way things worked in the past is how they will work going forward. But moving from the 20th century needs and constraints into the 21st century needs and opportunities cranks up the degree of difficulty of continuing to accomplish maintaining that 99.999% uptime mark. Changes are already occurring that require fundamental reconsideration of how the grid will need to function.

And that leads us to the target of my next post, The Grid. And more specifically my thoughts about the distribution grid, the 21st century pressures on it, and how it is likely to transform over the next decade.

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At the end of this past summer, our local power utility. Pacific Gas and Electric (PG&E), held an Innovation Day. During that all-day event they identified the challenges the next generation energy grid will present and the problems the utility will face in making the transition.

They documented 70 problem statements and asked innovators to submit solutions. The problems addressed the electric grid, the natural gas infrastructure, and the new power requirements that electrification poses for previous fossil-fueled energy consumers.

A group of us were particularly interested in the problems that focused on the electric grid and expanded electric use. We decided to develop a solution that addressed a number of the utility’s stated problems.

The focus was on transitioning the electric grid from its existing centralized design instead to a Distributed Energy Resource (DER) design. Now we have to admit that DER is not a new concept. It has been around for many years and most recently has become more important as the cost of solar, wind, and consumer energy storage been drops. This has allowed an increasing number of utility customers to install solar and storage solutions on their buildings. PG&E recognizes this trend and that its future depends on incorporating DER into its product portfolio.

Over the past 10 years we have seen the cost of installed residential solar drop 65% as the cost of the equipment dropped 85%. This has been driven by manufacturing efficiencies that result from increased volumes. We see a similar trend occurring with battery storage. Here both changes in chemistries and the efficiencies of volume production have driven the cost of stationary electric storage down. These rapid changes result from the rapidly growing electric vehicle market where battery sales have been increasing at 12%/year. This trend of cost and price reduction shows little sign of slowing down.

PG&E has a process called Integrated Grid Planning (IGP) that has remained virtually unchanged for the past 40 years in a period of minimal load growth. Power flowed in one direction. Expecting a 70% increase in electric load over the next 20 years, the utility needs to increase capacity while at the same time find ways to deliver on its promise to provide a net zero grid by 2040.

So, what does this mean? It suggests that DER will present a large capacity to augment the electric grid and help utilities achieve their goals.

Why Transition to Distributed Energy

In a previous post about Electrify Everything I had the epiphany that the EVs we have been driving will become the major consumer of electric energy. Granted EVs are much more efficient (about 3X) than fossil-fueled vehicles. But adjusting for the simpler design that the EV offers, that gallon of gasoline still carries about 30 times as much energy as the same weight in batteries. We consume LOT OF ENERGY to run our vehicles.

From my personal example, provided in Electrify Everything, I estimated that we will reduce the amount of energy we consume by 60% as we electrify our transportation and the appliances that provide heat by burning fuel. However, the electric energy replacing those fossil-fueled systems will exceed the electric energy that we use in our buildings today. This suggests that the electric grid will need to handle peaks exceeding two times their current design and that likely the loads will shift in time.

That latter thought, that demand for electric power will shift in time, is significant. During the summer at the beginning of this century the peak load period was late afternoon as air conditioners began to tax the grid. That has changed dramatically today resulting from the rapid adoption of residential and commercial solar. Now the high demand period is shifting to the evening hours. Several times a year, California ISO actually has a surplus of power resulting from the solar, the DER, installations during what used to be the highest demand period.

If we look at the pie chart below from the US Energy Institute, we quickly see the impact electrifying our transportation sector will have on the challenges for the electric grid. This is just one of the examples of how the load will shift in time.

Transportation accounts for 41% of our energy demand. Now imagine what the load might look like if we begin fueling our vehicles at home. When a large portion of California’s energy was supplied by nuclear plants which have minimal capacity to change output, there was a surplus of power available after midnight. But today, our most common surpluses are when the sun is brightest. But most vehicles are either in use or parked at work during this time. There is a clear disconnect between the time that energy is available and when it is most needed.

20 years ago, the primary method of storing energy to address the discontinuity between the time when energy supply was available and demand needed it, was by storing water at higher elevations. During periods of excess supply, water was pumped uphill. During periods of excess demand, the water flowed down through generators. This pumped-hydro has the ability to generate 3,960 MW as long as the water lasts. But the peak need in California in 2022 was 52,061 MW., well surpassing that pumped-hydro capacity.

California cars get the best mileage in the nation at 31 mpg. And we sell about 38,000,000 gallons of gasoline per day. That suggests that Californians drive approximately 1,178 million miles a day. If those all are exchanged for EVs getting 4miles/kWh we would need 295,000MWh of electricity delivered each day to fuel vehicles. With the California driver covering and average of 34 miles, it will take almost 5 hours on level 2 for them to recharge. If everyone recharged at the same time, that would demand 58,900MW from the grid. We double our peak as we electrify our travel.

That means we need both twice the supply we have today and twice the transmission capacity (larger wires and transformers) to deliver that electricity than exists today. So the question is not just whether we have the capacity to generate the electricity, but rather do we have a realistic way to deliver it were we to continue to use a centralized model.

Below, I picked a day this year. Not summer, not winter, but near the equinox to demonstrate the California’s sources of energy.

Renewables today represent the lion’s share of our energy source. But much like nuclear, there is little control over when the supply is generated. With over 17,700MW of renewables in the state, where 15,000MW of it is installed rooftop solar, it is clear this growing DER resource should be both a source of the electric energy we need and a solution to the distribution infrastructure problems.

Looking for a solution to harness DER

In my next post, I plan to describe the Scalablepower SmartStor solution that we submitted to PG&E. It does not focus on expanding solar, but rather how local storage and control of demand can be managed such that it provides benefit to the local user as well as the utility grid.

Hey, I’m not a purist - there are things that my friends know I do that simply cannot be reconciled with wanting to reduce my GHGs. So it might be important for all of us to recognize we can’t stop producing GHGs (unless we wanted to stop breathing), but we all could find ways to reduce the amount of energy we employ and rely on more renewable sources.

In 2006, besides recycling and diet changes, we invested in our first solar installation. It was a learning experience.

We selected the most efficient system that we could get and installed 2.5 kW of solar on our then home in Silicon Valley. At the time I was blown away with the check for about $80 we received from Pacific Gas and Electric each year. No electric bills and cash to boot. We were on something called the E9 schedule which rewarded us for having installed a solar system.

After a couple years, it occurred to me that this arrangement didn’t make any sense. How could PG&E afford to send me money for my energy and provide a service to me at the same time. They were both making sure that I didn’t run out of power and if I produced too much that they would essentially deal with storing it for me.

History has proven that indeed PG&E CAN’T afford to do that for everyone! Consequently over the past 17 years, the tariffs have consistently been changing in order to balance the need of incentivizing all of us to participate in collecting energy. while not rely on the utility paying retail prices for what normally they could buy at wholesale.

I also learned from that experience that I should never have paid for the highest performance panels and that just having panels did not make us any more resilient to power outages.

The only reason to get the highest performance panels is if you have a limited amount of space to install them. Well in a home with over 2000 sqft of roof, we certainly had plenty of space for panels. Getting panels with a lower yield and a much lower cost per kW would have made more sense.

And as a university-educated physicist, I should have been able to recognize that the power my panels produced at any instant in time (which varies constantly depending access to the sun) all has to be consumed precisely by my home. We had not installed batteries on that system. The only place the surplus from that system could go would be back to the grid. (If the power has no place to go, the voltage would rise and we damage TVs, computers, heating system,; whatever was plugged in.) Whenever the grid went down, the solar system automatically turned itself off.

OK, so here we are in 2023, 17 years later and quite a bit more informed. Our current home in SF North Bay has 6.7 kW of solar and 12.5kWh of battery storage. As mentioned in a previous post, both our cars are electric, our hot water and HVAC systems are heat pumps, the kitchen is all electric, and even our garden equipment is plugin. We made all of these changes after we had re-insulated the home in order to reduce the energy we use.

Now I am questioning if this was a great move. Are we using less energy? Is this costing us less, or is it costing us more? The later question popped up when last November we received a bill from the utility for over $600. That bill (which all solar-installed customers learn about) is the same annual bill which on my first system sent me the $80 check. It is the true-up bill.

I won’t go into why the bill looks like that. Though I can say I spent a lot of spreadsheet hours loading data in order to figure out how it was possible that we owed that. (It was possible.) But the exercise gave me an opportunity to compare how we used energy 15 years ago and how we use it today.

This leads us to the newest set of surprises.

We use a lot more electricity than we did in the past (about 3 times as much),
but we use about 1/3 the energy that we did in the past.

Our home in Silicon Valley averaged about 11kWh of electric consumption per day. This varied dramatically from day to day, but if you take the entire year’s consumption and divide it by 365, 11kWh is the result.

I was devastated when I completed the same calculation for our current home. After converting to LED lights, wrapping the outside of the home with between R12 and R20 insulation over the existing insulated structure, eliminating all thermal bridges, and replacing all the windows with high performance replacements, I expected to reduce the energy need well below the Silicon Valley home. After all, that Silicon Valley home had 100 linear feet of floor to ceiling window walls.

When I did the same electricity consumption calculation for the current home, adding both the energy we collected through our solar panels and the net electric energy provided to us by PG&E, I found we averaged 33 kWh/day. WOW!!! I had no idea!

How can it be explained?

It is amazing how little we think about the energy content and the volume of fossil fuels we use in our lives. I went back and pulled all the bills from this current home before the full electrification went in place. In that case we had natural gas water heaters and space heating; and we had gasoline powered cars.

Before the home was insulated, in a year’s time we consumed 548 therms. One therm of natural gas is equivalent to 29.3 kWh. Our natural gas consumption meant before electrification we were burning 44kWh/day of natural gas.

Then I considered the cars that we replaced. OK, I don’t have bills for them. We don’t think much about it as we pump the fuel at the station. But I can develop an estimate (remember, trained as a physicist). On average we drive 15,000/year. We are pretty conservative drivers - so our cars averaged around 45 mpg. In round numbers that is 334 gallons of gasoline a year that we burned. One gallon of gas contains roughly 33.7 kWh. That means our gas cars were burning an average of 31kWh/day.

So included in our 33 kWh we are absorbing the 31 kWh/day of driving and 44 kWh/day of heating for the house and water. The electric utility records from before the installation of our first heat pumps has been lost. But if we simply use the values from our previous, less efficient home of 11kWh as the base case, then we are comparing 33kWh to pre-electrification energy consumption of 86 kWh.

After electrification of our household, we are using 62% less energy today than when we were relying on fossil fuels as a heat and mobility source.

This 62% is an interesting number. In the book “Electrify:An Optimist’s Playbook for Our Clean Energy Future” by Saul Griffith, he maintains that by electrifying everything we can reduce our consumption of primary energy by 60%.

OK, here we are! We electrified one home and household and achieved a 62% reduction. Right On!

Additional Thoughts - are we ready?

This post does not explore the concern that the existing grid does not have sufficient capacity. Today I believe PG&E has a capacity to deliver near 94 million kWh/day.

PG&E has 4,800,000 residential accounts. If they exchange their gas cars for EVs and average the same 15,000 miles per year of travel as our household does, that would require 50 million kWh of electricity each day to power their electric cars.

On the home front, heat pumps in California run about 3.5 time more efficiently than gas heaters. Using our home as an example, we can multiply out that the 60% of PG&E customers converting from natural gas to heat pumps will represent an additional 36 million kWh/day of capacity.

There is a challenge ahead of us.

NOTE: A separate topic is the operational and lifetime cost difference between fossil fuels and electric options. This might be a future post or you can watch my short video as I explore this and why electrification is more valuable than meets the eye.

What’s next - dig in and see if we can find a way to get UN-confused.

I have this really nifty app that Sonnen (the Shell company) sent me that explains how my solar and battery system are working. I’ve been trying to see how I can increase our self-sufficiency. (As one REAL critic explained, self-sufficiency is not the only goal one might try to achieve. But that discussion is for another post.)

But as I review the results today I was really confused.

How can I have generated 15.7kWh so far today, and I have only consumed 16.9kWh, be just 53% self-sufficient? And why is there only 8.9kWh applied to my needs (energy world calls needs, demand)?

Looking at this diagram above, we can see the battery is discharging (the green line) throughout the evening. In my attempts to increase my self sufficiency, I have configured the battery to discharge from 4 PM (when the premium utility rates kick in) until 10:30 AM (when the sun usually starts reaching my solar panels.) With the goal through that period of minimizing grid imports, the battery is configured to allow discharge all the way to 30% while the grid is available.

As you follow the green line, today it only discharged to 40% until solar energy began to be collected (the yellow line). At that point the battery began to refill. The battery is a 12.5kWh pack, so with 60% discharged it needs 7.5kWh of energy to be fill back up. The solar array is just under 6.7kW, but this is late October, so that peak we see at 11:45 is just at 4.2kW. Any surplus solar energy not necessary to power the house begins to fill the battery.

The dog and I decided to find a new place to hike this morning and went for a drive. I kinda got lost, so the battery in the EV drained for 48 miles. The way I drive, that equates to about 12kWh of energy. When we returned home we plugged in the car to take advantage of the solar power available.

We see the demand (the blue line) changing dramatically as soon as I plug the car in. But the car doesn’t know about the limits of the solar array and so it begins to pull 7.7kW of energy to refill its battery. Over the time it takes to refill the car battery, the solar array averaged about 2.8kW, so the grid needs to supplement the supply to meet the demand.

Now I am starting to get a hint at why the self-sufficiency is so low. It has to do with the definition of consumption.

SolarEnergy - BatteryRecharge + GridEnergy = Consumption

And yes, the system does measure consumption directly. The ah-ha for me is that recharging the battery is not consumption, nor is the discharge of it supply. The battery’s machinations are nothing except a shift of the energy supply. The battery energy doesn’t care whether it sources from the solar or from grid supply. So it simply does NOT enter into the calculation of Self Sufficiency. But it does drain the supply that is used to calculate self sufficiency since that energy was NOT available to satisfy demand!

Let’s check and see if the numbers confirm this epiphany.

OK, up till now today (about 2PM) The house has been using around 300W/hr (5.2kWh/14hr) and the car took 12kWh. Adding those together (17.2kWh), we are pretty darned close to the 16.9kWh the app has reported. And we know that the car was going to drain at least 7.9kWh from the grid to supplement the solar. That’s where we see most of that grid contribution of 8kWh.

WOW! this all matches well with the self consumption reported.

The curious part to watch for the remainder of the day, up till midnight, is how the Self Sufficiency increases. We should have a little more demand that the battery will continue to offset after we reach 4PM and the battery is allowed to discharge.

But in any case, the 7.9 kWh supplement required to charge the car will keep self sufficiency from reaching to 100%, That is because regardless of the past experience, the battery is not allowed to discharge in excess of the realtime demand.
(It can never catch up. Kinda like the 5 year old can never become older than the 7 year old regardless how long they each live.)

OK, so now I stand Un-confused.

I am at that age of retirement and bored with the thought of not working everyday. (I bet there are a lot of people like that in the world. ) I enjoy thinking. I enjoy making things work. I have to admit I don’t enjoy focusing on just one thing at a time. (That might explain my tendency to lose jobs where people insist that focus is necessary in order to get things done.)

If I listed the positions and jobs I have had, you might consider that I had no consistent career. (Hmmm lack of focus…) But in reality every job had one thing in common. I was a system designer. I kind of think that to be a system designer, and you want to design really useful systems, that you should not be dedicated to focusing. You have see everything around you and how it can fit together.

I found focusing is a bit like looking at the world with just one eye. You can se the things in front of you, but what about the stuff on the other side of your nose? And, unless you are moving around a lot, how far away are things.

So maybe I don’t focus nor do I stay still a lot! I want to see everything, see how far away it all is, and basically see how it all fits together.

Today I am interested in determining how we can reconfigure our lives so that we those things we enjoy while live within the budget this planet has provided us. Weird… Here I am having lived in 2 separate centuries. I find we have 20th century systems trying to solve 21st century problems. It might be possible… but I really doubt it.

The reason for this substack is to explore thinking, ideas, observations, and see if anyone else REALLY wants to criticize those thoughts - and set me straight.

And if I don’t focus on environmental issues, you will have to get over it.

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