The Deep Future of Energy, Part 3
And Now, The Grid of the Future...
We have spent the last two weeks on very deep dives into the technologies, economics, and physics of the energy grid. See part 1 here that talks about energy producing technologies, and part 2 here that talks about energy storage and transportation technologies.
This third and final part is the payoff. I didn’t feel that I could share this vision for a realistic, high-performance, almost-zero-carbon global energy grid without explaining all the reasoning behind it. Now that you understand much more deeply about the things that matter for an energy grid (flexible, reliable, low maintenance, economical), you can assess for yourself whether this plan is world-changing. After reading the first two articles on the deep future of energy, you have the toolkits you need. So let’s go.
The Global Grid of 2072
I will describe here a dramatically upgraded global energy grid with:
Flexible storage
Flexible energy levels and frequencies
Flexible geographic energy sourcing
Flexible long-distance transportation
Ultra-high reliability
Minimal to no dependence on fossil fuels
All using technologies we have in-hand today, just scaled up and used wisely
But first, let’s look at the one part that won’t change.
Regional and Home Transmission and Distribution
We now live in an AC world. All the electricity to our homes is AC, meaning that the current (and voltage) in our electrical lines varies like a sine wave at 60 or 50 Hz, depending on where your live in the world. There are also variations of the voltage level going into your house. In America, most of our home outlets are at 110 volts and all our power is at 60Hz.
In 2072, we probably won’t see this change at our homes, because the inertia of the standardization of all the electronics we use around our homes and offices will probably keep things as they are (we can't get everyone to switch out their toasters all at once). And thus the neighborhood and city distribution systems bringing power to our home will probably still be AC as well. Remember last article when I said that transmitting power at a high voltage led to way less power line losses? Well, when your power is AC (instead of a steady voltage-current) of DC), then you can use something called a transformer. A transformer can take time-varying voltage and current and run it through a pair of coupled coils that allows you to step up the voltage to high levels (say 60,000V) for long-distance transmission or step it down to safe levels (110V) for use in your home. This is really useful, and it works well for cities, neighborhoods, and regional areas.
In order to make our vision of the future most feasible, we won’t change this, and will be using the exact same infrastructure we already have for the last 50-100 miles of energy transportation and distribution, from the regional down to the home.
As we will discuss below, solar panels and batteries at homes will be a significant part of the future grid. The neighborhood, city, and regional grid that already exists can co-exist with widespread solar + battery home use, with only a few minor upgrades. There is no reason to make any large changes here.
No vision of the future is likely to just throw away the tens of trillions of dollars’ worth of functional infrastructure we already have. It actually works really well…let’s use it!
DC Energy Pipelines
As discussed in the last article, High-Voltage Direct Current (HVDC) transmission lines enable low-loss power transmission for as long as 6,000km with only 15-20% losses. If losses were allowed to go higher, say 33%, then those lines could be 10,000km long.
I propose building out a global infrastructure of long-haul HVDC lines.
These lines will be capable of bringing energy from lower-latitude solar-rich areas to high-latitude solar poor areas. They can also bring off-shore wind farm energy from coastal and northern-latitude areas to interior and lower-latitude areas.
One of the biggest problems with wind and solar is of course their intermittency. And that intermittency is not only hour-by-hour and in small regions. Sometimes after a big storm passes, winds go to very low levels across large parts of entire continents for weeks at a time. And there are areas of the globe the size of India that can find themselves under very cloudy conditions for a month at a time. There are even areas that have poor wind and solar prospects for much of the time, like China.
HVDC “pipelines” can act to distribute energy globally in a way similar to how trans-national oil and gas pipelines distribute energy globally now. Central Europe has little natural gas, but they use a lot of it because pipelines coming from many thousands of miles away enable that consumption. In the same way, HVDC trans-national “pipelines” can bring solar and wind (or geothermal or tidal) energy across entire continents.
But the HVDC pipelines can carry MUCH more energy than oil and gas pipelines (up to tens of Gigawatts each!), and dozens of them can be laid next to each other with no interference or problems. Further, HVDC pipelines are two-way, and the energy flow changes happen at 2/3 the speed of light1.
Critically, long-distance HVDC lines provide a way to enact geographical diversity into the electricity consumption market. In one day, residents of Dusseldorf, Germany might use energy from Norway, Algeria, Saudi Arabia, and the Caspian Sea, perhaps all at the same time.
In the same way that we don’t care where our streaming website is hosted, we won’t have to care where our energy is sourced.
The HVDC pipeline system will enact a global internet of energy, treating sources like fungible commodity providers.
When I first considered this, I worried about the political logistics of having continuous infrastructure across multiple different countries. But then I realized that trans-national oil and gas pipelines operate across the globe just fine. We can use the same frameworks for maintenance and cost-sharing that we do for them. Or we can use a framework more like that which is used for trans-national fiber optic data lines. One of the most important things about the HVDC lines that separates them from the oil and gas pipelines is that there are many, many more sources of solar and wind power across the nations of the world than there are sources of oil and gas. If one country starts to cause a problem with supply or threatens to mess with the HVDC line in their country, they can be replaced as a supplier or routed around transmission-wise.
The internet currently has many “extra” fiber optic data lines laid around the world. These exist because it’s easier to lay down two or three cables next to each other during one boat trip than to make three separate boat trips (among other reasons).
We can lay down significant extra dark cables of HVDC lines, to help supply future or sudden increases in power demand at distance. And remember, those distances can be up to 10,000km, or a quarter of the way around the globe. In each direction.
The Mighty Thyristors
But wait, how can we have AC infrastructure in our cities and neighborhoods if we are getting a lot of our energy from HVDC lines?
Oh, the problem is much, much worse than that. Different countries run at different frequencies (50 or 60 Hz), and even countries near each other that are all at 50Hz might be at different phases (meaning their sine wave peaks and troughs aren’t lined up). What happens if you did have a line that connected to both different-phased countries, or is connected to both a 50Hz and a 60Hz grid?
Fires. Lots of fires.
The grids would basically catch fire at weak points and automatically shut down, likely with a significant amount of equipment damage. When the frequencies and phases don’t match, everything gets overloaded and goes haywire because the energy is no longer flowing coherently, but rather becomes “peaky” and “jumpy” in very damaging ways.
So how can we possible have a single HVDC super-pipeline service multiple countries with varying grids? It’s not even AC, and if it were, there would be fires.
Enter the mighty Thyristor.
Thyristors are some of the first silicon devices created, along with the more-famous transistor. These are basically solid-state switches, meaning there are no moving parts. They can be switched on and off very quickly, just like a transistor. But modern thyristors can have megawatts of power flow through them.
And thyristors can convert electricity from AC to DC, and from DC to AC.
I propose using thyristors at each grid to tie into the HVDC lines, converting electricity to the correct AC frequency and phase for each different grid.
Thyristors are already the go-to technology for converting energy to and from the few existing HVDC lines. But I am saying to use them trans-nationally to keep grids connected but independent.
Imagine having a large HVDC line passing through the Netherlands, Belgium, and Luxembourg. Let’s just say that they each have a different grid at different phases. You can’t tie those grids together2. Each of those countries can have a tie-in to the HVDC line, a special station or set of stations. At each country’s station, they use giant stacks of thyristors to turn that HVDC power into AC power at the frequency and phase that matches their grid. Each country’s own thyristor bank can simply create the AC frequency and phase that best suits them. As long as they have smoothing capacitors3 and feedback-limiting diodes4 and other equipment to prevent “contamination” of voltage and current wiggles back onto the HVDC line, then whatever the Netherlands does with the HVDC power will have no effect on the other downstream countries of Belgium and Luxembourg. Except of course there is less power as you near the end of the line, potentially. But then the supplier at the source of the line (say, a wind farm east of Denmark) can just put more power in to match demand.
Thyristors allow multiple different grids to be fed by the same HVDC line in a very flexible, independent manner.
Thyristors also enable energy sources, such as wind farms, to turn their AC power into HVDC power. So any large hydro, tidal, or wind energy source can just feed into the network of HVDC lines, and thyristor banks can be set up to help manage the power flow into the network (making sure the correct currents and voltages are maintained). There are some losses, between 5% and 10% in this conversion process, but this is usually considered acceptable.
The biggest winner in the HVDC + Thyristor paradigm, however, will be solar power. Thyristors don’t just convert DC to AC and back. They also can be used to construct DC-to-DC converters, which boost the voltages from solar farms (typically in the hundreds or thousands of volts) into the megavolt range needed for long-haul HVDC.2 This allows solar stations in the Sahara to actually, feasibly supply Europe with green energy, even during long winters.
Moderate Amounts of Grid Batteries
In the last article, I postulated the use of an 18TWh battery for America, the Eagle Screech battery. This would store about 36 hours worth of energy for America, to help enable a transition to using intermittent wind and solar energy.
But if we really want to transition to solely using renewables using the current grid, we would need around 3-5 Eagle Screech batteries, because sometimes there are extended periods of clouds and no wind. This would just be for America, and the world would need around 6 times that many batteries. We are talking on the order of 300-400TWh globally, which is far, far from feasible.
But the HVDC + Thyristor paradigm allows for extremely wide geographic variability in energy sources. It is very unlikely that the sunshine and wind will both fail over half the globe for weeks. This drastically reduces the need for grid battery storage down to 0.5 to 1 Eagle Screech battery for each America-sized energy grid. But it doesn’t bring that need down to zero. Remember, grids must be impeccably reliable, with greater than 99.9% on-time and no brown-outs.
But the combination of distributed half-to-full size Eagle Screech batteries will allow for a full and permanent transition to renewable energy sources. While that is being built out, hydro, natural gas, and nuclear power can help smooth the supply to meet changing daily demand and variable wind and solar supplies.
That said, I strongly suspect hydro power will be reduced as people desire to restore rivers, and nuclear power will go down as existing plants age and new plants face massive regulatory hurdles. So we should build out the battery infrastructure as quickly as possible.
I propose deploying around 100TWh of grid battery storage globally.
While this seems like a lot, it is about 1/3 of what would be needed to help the current grid transition to renewables. And it could actually be accomplished with known battery technologies and known reserves of lithium and nickel. It would just take about 40-50 years to build out. But it can be done with today’s technology.
America uses around 16% of the world’s energy supply, so we will need 4-6 Eagle Screeches (around 100TWh) of batteries to wean us off fossil and nuclear permanently. And of course, as those batteries age, we will need to replace them. These initial batteries will likely be lithium ion batteries, and this can be done in 30-40 years. If flow batteries can become 30% cheaper than lithium batteries, scaling up production of flow batteries might happen decades faster than that due to their liquid storage format.
Distributed Installations of Solar and Batteries
This is something that is happening and will continue happening almost regardless of what any government or utility does. People will be installing more and more solar panels on their homes, and when battery prices get about 40% cheaper than they are now (projected to be in just a few years), people will start buying batteries for their homes. Electric cars will also be used as power backup for homes, and an energy-fungible bank of power at night for use in the neighborhood/city part of the grid, if two-way inverters like the Tesla Powerwall are utilized.
The reason I bring this up is simply that this will make the future grid even more robust, as less power will be needed to be transported in the HVDC lines and passed through the thyristor banks. 10kWh of power generated at your home is worth 12.5kWh generated far away and transported to your home, because of power losses.
Also, governments and utilities won’t have to buy as many grid-scale batteries as more and more houses have their own grid-connected and potentially grid-feeding batteries.
It is also worth noting that in a decade or so, new construction may start to have integrated solar roofs and walls become more widespread, as solar panels are about to become as cheap as many of the construction materials used for roofs and walls.3 This will also make the grid much more robust, eventually. But before we have our two-way HVDC pipelines and Eagle-Screech-sized batteries, we will need to use other energy sources, especially natural gas plants, to smooth out the supply/demand curves created by this increase in variable solar power being plugged into the grid.
The Financial Grid Stabilizer
HVDC pipelines, grid-level thyristor banks, and moderately large grid-scale battery installations address all the physics and engineering needs of the grid of 2072. These novel applications of existing technologies will make it so that everyone always has access to electricity.
But at what cost? Algerians, with their massive solar farms, may pay next to nothing for electricity, while Mongolians might find themselves facing some of the highest costs on the planet. Industrial processes use a lot of electricity, and high electricity prices can be absolutely oppressive to large swaths of populations, especially the poorer people in any country.
With global supply secured, though, there is a wonderful way to levelize the cost of power across the globe. And if you have been reading this blog a while, you already know exactly what that is.
I propose using cryptocurrency mining at low cost energy sites to levelize the global cost of electricity, reduce the total amount of energy transmission, and incentivize energy supply build-out.
In our previous article “Bitcoin Is Green Energy” I described how cryptocurrency mining (it doesn’t have to be bitcoin) can be used to transfer large amount of energy across the planet instantly:
If you have a place, like Algeria, with a surplus of cheap energy, you mine crypto there.
Then you sell the crypto to a place with expensive energy, say Mongolia.
The Mongolians, instead of smelting aluminum ore, which takes a LOT of electricity, will simply use that cryptocurrency to buy refined aluminum.
The Mongolians can then build cars or whatever at a cost cheaper than if they refined the aluminum themselves, AND it kept the grid from having to actually, physically transport that power.
Rinse and repeat for any industrial or commercial process than requires a lot of electricity.
Using cryptocurrency as easily-transferrable and dense units of electricity, only the blockchain transfer needs to be sent across the planet, not the electricity. The intensive local demand on the physical grid far from the energy sources will be lowered, and the grid will thus be cheaper and more stable for everyone.
This fungibility (ease of exchange) of money and electricity globally will move actual, physical electrical use, on average, closer to the best, cheapest sources of electricity. It will also further incentivize the creation of cheaper and cheaper sources of electricity, organically subsidizing investment in energy production infrastructure.
This crypto currency energy-trading paradigm is not necessary to make this future grid work. But I do think it will make it work better, and the benefits will result time and transmission shifting that will create new, stabilizing free markets of energy that currently don't exist.
Final Summary
The globe will be encircled by ultra-long distance HVDC energy super-pipelines.
Each country will be able to tap into these lines to add in or take out energy based on their surplus or need that they have, dynamically. This is enabled by thyristor (and similar) solid state technology that allows for efficient and high-power conversion of AC to DC and DC to AC electrical power.
Thus, the existing local AC infrastructure will still be used, basically as is (though upgrades of many types will of course happen).
Large grid-scale batteries will be installed around the globe. We will need around 100TWh of battery storage to completely move to renewable but variable energy sources.
Wind and solar will “win.” Other zero-carbon sources such as hydro (dams), tidal, and geothermal may have small contributions to make, but they will not be dominant sources, and they will likely shrink proportionally over time.
Homes and commercial buildings will install solar panels and batteries until a significant proportion of buildings will have these energy producing/storing technologies. This doesn’t need to be legislated or incentivized. The costs of solar and battery tech will make it a no brainer for many parts of the world.4 This widely distributed source and storage of solar power will cause grid growing pains over the next few decades, but will eventually make the grid more stable and reduce the need for utility scale battery and solar installations.
Nuclear will eventually decline due to regulatory difficulties in most countries. China and France may be large and important exceptions. More nuclear accidents will likely happen as the existing plants continue to age but stay in use, driving further regulatory restrictions.
Natural gas turbines will be an extremely important technology to aid in this transition for decades to come. They will eventually be slowly phased out once the ultra-long-distance HVDC and battery infrastructure is in place, in the late 2040s or 2050s.
Cryptocurrency mining will be widely used to levelize the use of electricity for manufacturing and other physically electricity-intensive activities. Cheap-to-produce electricity will be mined into cryptocurrency and this mechanism will make energy fungible with basically zero transmission losses or costs, globally. This stabilized the grid and incentivizes the creation of more supply, lowering the electricity costs for everyone.
Grid Optimism
I am incredibly optimistic about Earth’s energy future. I don’t think that this concept needs to be pushed to come into existence. It makes too much sense *not* to happen in this way.
The HVDC + Thyristor + Battery + Crypto grid will be amazing.
No new technologies are needed. No new legal frameworks are needed. No trans-national grid coordination is needed, except the agreement to host and use the HVDC lines (like pipelines are now). This grid is supremely resilient, reliable, and the cheapest possible way to move forward toward a zero fossil fuel future.
And while I reemphasize that no new technologies are needed, this grid is also future-proof. If fusion comes online, or some other new type of energy source is discovered, this grid is ready to on-board it, no matter how intermittent it is, no matter whether it’s an AC or DC source of power.
This grid solves global warming, lowers energy cost, and literally will empower all corners of the earth.
Thank you for taking this Deep Future of Energy journey with me. I hope you enjoyed it.
The individual electrons don’t move very fast, but the change in power (if you change the current level or switch its direction) will propagate through the line at 200 million meters per second via the electric fields in the cable.
There are other technologies besides thyristors that can also accomplish megawatt DC-to-DC conversion, and this is an active area of research. But many, many designs use thyristors as the core components or at least as part of the more efficient designs.
“The price of solar panels has fallen so much, says Samuli Rinne, an energy engineer heading up an EU smart-energy project in Oulu, that business owners have can put panels on their office buildings’ southern facade at a cheaper cost than some of the more expensive building materials. Solar sector representatives in Europe say that while just five years ago the lion’s share of the price of a household solar system was the hardware (panels, inverter, battery, digital management program) and not the installations costs, today it is the other way around. ” https://insideclimatenews.org/news/24022020/solar-finland-nordic-renewables-sanna-marin-climate-targets-turku/
Electric cars will be a contributor to the total power storage of the grid as well.