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· 5 min read

The abstract to my master's thesis in nuclear engineering titled: Design for Cost Methodology Applied to High Temperature Gas-Cooled Reactors

RX Power
Figure 1 Design space under random sampling showing effect of RX Power on the Levelized Cost of Electricity.

SpaceX’s Falcon 9 is like a Toyota Corolla – an order of magnitude cheaper than competitor’s “high performance” rocket systems, the Ferraris, but achieving the same basic transport requirements with greater reliability and safety. Before Falcon, space launch was a Ferrari-like industry, with handmade, highly specialized, extremely expensive vehicles targeting government customers and fully complicit in the inefficiencies of government contracting. Similarly, the nuclear industry produces and still designs Ferrari-like fission reactors, with high performance metrics in terms of power density and unit power, at a megaproject scale, but with high system and operational complexity, extreme development cost, numerous part counts, and very low production and deployment rates that still require human-machine interface to meet societal safety objectives. The demand for nuclear Ferraris in the U.S., particularly within non-traditional energy utilities is very low, as few competent utilities want unique reactors with such high capital costs, running at such high power that low probability accidents can have offsite consequences. Where is the nuclear Corolla?

· 5 min read

Spherical Eye-ware Concept

Reduced Distortion Protective Eye-Ware

This is part of the design thesis aiming for

  1. Physically derived functionality
  2. Conformity to human needs
  3. Reduced constraints from manufacturing and cost

· 14 min read

The general public and even most nuclear engineers do not understand how easy it is for nuclear fuel to fail. Since the dawn of the nuclear era, nuclear fuels have been designed and built to meet only a small portion of the full requirements. This was due to material and technology limitations as well as costs. The only economical and practical way to use nuclear material for power has been simple fuel oxide pellets in metal cans.

That is now changing with the introduction of TRISO particle based fuels and use of advanced radiation tolerant ceramics. In this post, I will explain the performance goals of nuclear fuel and then show how normal fuels compare relative to TRISO based fuels.

Still there's a limit to what I can do with words. I can write all about nuclear accidents and the performance characteristics of traditional fuel compared to new TRISO-based fuels, but people often don't get it. The technical discussion of materials in nuclear reactors and how they affect fuel performance is not straightforward. But the practical differences between traditional and TRISO-based fuels would be plainly obvious if we could observe the fuel forms in action. We can't visually observe nuclear accidents as cameras can't survive the radiation, but we can show what happens using animations. So I rigged up a quick animation showing how traditional fuel and TRISO/FCM fuel look like as they encounter the same or similar conditions. I've made simplifications for the sake of comparison and illustration, but the general idea stands that during severe accidents, traditional fuel will fail to the point of melting and vaporization while TRISO/FCM fuel remains solid and functional.


· 12 min read

As a side-project, I collect and maintain information on upcoming nuclear energy extraction systems. Having it all in one place makes it useful for the public at large, policymakers, and scientists looking for a better understanding of the unfolding nuclear technology landscape.

There are now many designs, perhaps as many as 100 that are actively developed with more than a handful of people. To an outsider, these designs are all the same or arbitrarily different. Neither perception is true - there are important differences concerning cost and safety that should be more widely discussed.

· 8 min read

Colloids

I started my PhD at MIT in September of 2019. USNC was in a state of belated fundraising, and I spent most of my time working on that while just barely getting by in classes. I managed to avoid get suckered into a research project until November, when the apparent slacking started to look egregious, and USNC had finally hit it off with an excellent investor.

The project was on colloids for single-phase heat transfer with Dr. Bren Phillips and Prof Jacopo Buongiorno, as well Abdullah Osman, my friend in his last year as an undergraduate. Later, Minuk Jung, a new graduate student in mechanical engineering, would continue the project. The idea was to define and predict heat transfer performance for colloids in single-phase cooling applications. And then design, make, and test a colloid to maximize that performance. In the end, I learned some plumbing and made observations that did not match predictions. Here's a brief summary of the 100 page report.

· 3 min read

Nuclear Energy for Very Long Term Applications

We should build a nuclear powered monument that could last several thousand years. A reminder to future generations, human or not, that we existed and we thought of them. And I want it out in the open – not like that silly 1000-year clock buried in a hole in the middle of nowhere in Texas. More like the Pyramids or the great churches from our past. What should it be and how will it be powered?

Nuclear Powered Lighthouse Monument

· 15 min read

This is a TRISO particle from Ultra Safe Nuclear. The central sphere is a nuclear fuel like Uranium Carbon Oxide (UCO), and the shells are made of various ceramics.

· 22 min read

High temperature gas-cooled reactors (HTGR) come in basically two flavors: prismatic cores and pebble-bed cores. Both use graphite moderator and TRISO fuel particles to make the core which allows the reactor to reach high temperatures and handle accidents with relative ease. Both use helium to cool it, which allows thermal applications up to 950°C and power conversion efficiencies of 40%-55%, compared to just 300°C and 30% in water-cooled reactors. They differ in the geometry and form factor of the moderator and fuel which leads to significant differences in size, operations, and technology roadmaps.

In prismatic cores like the Ultra Safe MMR or Japan's HTTR, graphite is formed into chair sized hexagonal blocks with holes for cylindrical fuel pellets and separate holes for coolant channels. The core is maximally packed and nothing moves. Refueling the reactor involves swapping out the graphite blocks.

In Pebble Beds like China's HTR-PM or the very similar X-Energy Xe-100 design, the fuel and graphite are packaged as balls (called pebbles) that are poured into the reactor from the top and emptied at the bottom in a continuous fashion like a gumball machine.

Pebble Bed and Prismatic HTGR

· 16 min read

No - it's not "too cheap too meter." But it also shouldn't be prohibitively expensive to construct. Estimating nuclear energy costs compared to other energy generating assets is challenging and necessary to make financing decisions. We just have to be aware as to who has their fingers on the spreadsheet. Is it a wind and solar zealot, a fossil profiteer, or a nuclear startup? The following is a little exercise to see what the cost limits might be for nuclear energy.

· 8 min read

Renegade power users: ditching a crumbling energy system

Look at your electricity bill. It's way higher than the Levelized Cost of Energy (LCOE) you see on Lazard, EIA, or elsewhere. The obvious reason is price versus cost - the utilities and hardware vendors need profits. Fine, but there's more, and it should make us consider abandoning the large centralized grid system altogether. Here's an example from my last bill. The cost of of the electricity is less than half of the bill!

· 37 min read

Fusion is generally touted by many as an energy "Holy Grail." Indeed, it appears to have similar qualities, being both perpetually elusive and miraculous, able to solve all mankind's problems. Media reporting tends to discuss the benefits of fusion with misleading and false statements and no discussion of fusion’s negative attributes. The financial and practical perspective of fusion based power is missing.

· 5 min read

Kirstov [1] lays out two possible scenarios for a restructuring of power delivery that addresses potential complications from increasing distributed energy resources (DER) on a grid that has historically been powered by a small number of centralized large-scale generators. How will efficient markets be run with so many energy sources? The first scenario is the so called Grand Central Optimization, a top down scheme in which DERs participate in whole sale markets, and the centralized TSO sets market prices and directly controls all the DERs and perhaps even has a hand in controlling the demand side.[2] The authors find such a scheme intractable due to the high level of detail and control required by the centralized authority to meet its operational requirements. The problem is just too big and complex. It may be a case of “commies with computers” in which starry eyed advocates believe computational power and sensors will finally vindicate Marx. Instead, the authors favor a bottom up decentralized scheme called the Layered Decentralized Optimization in which each segment of the grid is lumped together at the DSO level, and DSO’s communicate with TSO through a single node. This makes each DSO responsible for delivering power to its users by balancing its DERs with imported energy from the TSO. A TSO would be unaware of all the DER data and demand within the DSO and would only need to respond to each DSO’s bids and asks. Essentially, the authors propose separate layers of the grid that have simple communication and separate responsibilities, knowledge, and decision making to make a tractable grid that can support increasing DER and could scale indefinitely.

· 2 min read

The Hertzsprung–Russell diagram (HR Diagram) shows the status of stars in a cluster, represented by points for each star defined by temperature or color on the x-axis and luminosity (energy production) on the y-axis. From a cloud of gas, most of the stars in a cluster will form around the same time and constitute a population of stars of different mass but roughly the same age. According to their mass, the stars will then move around. Brighter and hotter stars are on the top left.

Animated HR

· 8 min read

Sports are boring. We need something new. I present Barf Ball, conceived during a mechanics course in undergrad.