Saturday, August 23, 2025

Silvermines Hydroelectric Energy Storage Project versus batteries

Pumped storage is cool. We have too much energy at night and not enough at peak times. So saving some electricity up is a good idea. 



One such scheme is €650m hydroelectric energy storage which will be able to store as much as 296 Megawatts (MW), with a daily storage capacity up to 2,175MWh of electricity. And employee 50 people long term.

It is just in the process of getting planning permission now. So it probably wont we operating for 7 years based on experiences elsewhere

Pumped storage has advantages of batteries. It doesn't go on fire. And the turbines last about 50 years not the 15-20 that batteries last. The initial infrastructure costs are high but once built it is cheap.

But just on the face of it how much would a battery version of the Silvermines project cost?

Technology €/kW (power) €/kWh (energy) Notes
Pumped storage hydro (PSH) ~2,000–3,000 €/kW ~100–200 €/kWh  Civil-heavy, very site-dependent; long life (80–100y). Costs stable for decades.
Lithium-ion (utility scale, LFP) ~400–600 €/kW ~80–120 €/kWh  Costs have fallen ~90% since 2010; China auctions hit <€50/kWh module-only. Life ~15–20y, ~6,000 cycles.
Iron-air (Form Energy target) ~1,700–2,400 €/kW ~20–30 €/kWh Still pre-commercial; very cheap energy, but low efficiency (~60%) and expensive per kW install (slower response). Life ~30y.

Iron-air batteries are inefficient and not widely used yet but they do get around the fire issue that worries people with lithium ion batteries. Lithium batteries have had a long term trend of more than halving in price every 5 years



It looks to me that at the moment pumped storage and batteries are about equal. Given how batteries keep getting cheaper though it is probably the case that by the time the Silvermines project completes they will seem to be the better option.

Monday, August 11, 2025

The best Worlde Words for the Lazy

 If you pick early words in wordle that have a lot of the commonly used letters you are likely to get to the correct word guess faster.



But say you were lazy and want to use the same 2 or 3 words all the time and then look at what letters hit or nearly hit to find the next word to guess. 

the best pair of words is 'raise' and 'clout' which leaves an expected remaining 5.1 words that could be the answer given what letters hit and near hit.
And the best 3 words are 
raise clout nymph which leaves 1.75 words on average that could still match the patters you will have seen.

These won't be as good as Crane followed by optimal picking of the next word given pattersnt hat were hit. But it will be pretty close and good for the lazy.




Friday, July 04, 2025

Grid Batteries could pay for themselves in 18 months in Ireland

I think grid batteries could pay for themselves in 18 months in Ireland. In January I calculated this as taking 3 years. 

Solar in May and June were enough here that it caused a bigger drop in wholesale price than usual during the day. You can see this as electricity prices drop below night time prices during the afternoons now.

This means that if you have a cheap enough battery it is economically feasible to buy at night and sell at 7am. And buy again at 2pm and sell at 8pm.





The recently set record-low tender price of €44 per kWh of battery storage, a one-kilowatt-hour battery following the May–June 2025 Irish spot-price spread would recoup its capital cost in  about 16 months on a gross basis, or  about 18 months after allowing for 90% round-trip efficiency. 

This is buying every night at 3am. Selling at 7am.
Buying again at 2pm and selling at 8pm. Losing 10% each time.
If you were clever and you could predict the best time that day to buy and sell for that day. Not just a do this everyday at this time strategy. These correct predictions would increase this profit. and reduces the payback time to 13 months including round trip losses. 

This wrongly assumes the all months are sunny like May and June were so spread persists year-round and excludes maintenance, inverter, and degradation costs. But also there is a lot of free electricity you would not have to buy at the wholesale price. ''2024's wind dispatch down rate is 14%'' means 14% of the time (usually winter nights) the electricity has no price and is not put onto the grid. Storing that, at your wind farm, and selling it in the morning is higher profit than our May/June calculations. Which would offset some of the lower profit from the lower solar then.

This is a rough calculation using Chinese battery prices but still it looks like a battery asset with a long lifespan is paid off in 2-3 years.

Code for this analysis is here


Solar has been doubling every 3 years for a long time. This graph might give some idea of what 2026 and 2027 will look like. The higher the peaks and troughs the higher the profit in storing the power.

An analysis of the last 365 days assuming knowing the perfect time to buy and sell electricity gives enough profit to pay for the battery at the Chinese tender prices. 

Period analysed: 2024-07-03 → 2025-07-03 (365 complete days)
Total profit: €45.01 per 1 kWh



Sunday, June 29, 2025

Lido in the micro nation of Pimlico

I watched passport to Pimlico. A 1949 fantasy about the ability to buy fruit, clothes etc without rationing.

The post war labor government that introduced the NHS kept strict reasons and export controls. The film is effectively wish fulfilment about these being removed.

The 19 families in the besieged nation, in the bombers out ruins off Post WW2 London, build an outdoor swimming pool. Something Dublin can't do now




Saturday, May 17, 2025

Euclid, Fermat, and the 65537 Reasons We Have Never Drawn Their Last Shape

 1. Straight Edge and Compass Euclidean Constructions

From the time of ancient Greece, geometers have been fascinated by what can be built using only two tools: a compass and a straightedge. These "Euclidean constructions" formed the foundation of classical geometry. You can copy a line segment, bisect an angle, draw perpendiculars Euclid's Elements are full of constructions and theorems that are built from these two tools.

But some polygons cannot be drawn this way. A regular 7-gon is impossible. Why? Because the set of constructible polygons is tied deeply to number theory, to Fermat primes.

2. Fermat Primes and Drawing Them

A Fermat prime is a prime number of the form


Only five such primes are known: 351725765537

Carl Friedrich Gauss at age 19 by proved that a regular polygon with sides is constructible if and only if is a product of a power of 2 and distinct Fermat primes. This means a regular 65537-gon is theoretically constructible.

One mathematician actually attempted to do it. Johann Gustav Hermes spent over a decade and 200 pages , detailing how to construct a 65537-gon using Euclidean methods in Ueber die Teilung des Kreises in 65537 gleiche Teile  in 1894. 

3. The 65537-gon

If you tried to actually draw a 65537-gon on a circle the size of the Earth (with of 6,371 km), each side would be approximately 611 meters long. Which means on a flat lake one side of the 65537-gon would not follow the earth's curvature by 3cm. A 65537-gon would be 3cm per 611 meter side off being a perfect circle. 

No one has ever made a by hand 65537-gon because it would just be too involved. though Hermes did spend ten years working out how it could be done in principle.


A 65537-gon (not a circle)


4. A Machine to Draw It for Us?

Could we build a machine that uses only a compass and a straightedge, like Euclid himself? Plotters could draw the 65537-gon by calculating angles and coordinates, but Euclid has famously tough lawyers and anyone making his shape not using his methods is likely to be mired in law suits




Such a Euclid Geometry machine would have to:

  • Set distances using a mechanical compass

  • Draw arcs

  • Align a straightedge through marked points

  • Draw straight lines with a pen

  • Combine these steps tens of thousands of times

It would follow the ancient Greek rules of construction.

This would be rock hard to make and not practically useful. It would involve, aligning a  ruler through two points. Resetting a compass to exactly the distance between two previous marks, which is mechanically fiddly. Detecting intersections and points on paper. All of this is simple for Ancient Greek humans but not for machines.

And yet, it would be beautiful. It would make visible not just the result of geometric thinking, but the process. A Euclid-bot wouldn’t just draw geometry it would demonstrate it.



There are cool online geometry tools but something about plotters and physical drawing things still appeals. Maybe it would be possible to make a ruler and compass wielding machine that could finally draw the 65537 sides of the last Polygon.



Saturday, May 03, 2025

Shock as Ireland goes mainly solar

 

In the Summer of 2026 there will be shock reported when solar energy supplies the majority of the power to the grid. 

When utility-scale solar reached a record output of 719MW during the early afternoon on August 31, rooftop solar is also estimated to have reached a record high output of 399MW

Demand at that time was 4300MW.




This won't happen this year. but I think it will in 2026 and when it does people will 
1. Claim this is a surprise
2. Ask about what happens at night
3. Ask about what happens in winter (which is actually a reasonable question)

38% annual growth rates of solar means that it will go from 50% at noon on the sunniest day of the year to near 100% at 4pm on a good day in May in a few years.

Drawing the US flag

 

 What happens to the US Flag they add more States

They have always added more stars sincde the original 13 up to the current 50.
There has been talk of Puerto Rico and Washington DC being added for some time. And recently Trump has been talking about adding
 Panama Canadian and Greenland.

Python Code Works

Here is some code to make a flag. 
The line to change the number of stars on each line is

layout = [10, 10, 10, 10, 10, 10, 10, 10] #60

the code is here and it is based on this original article.

51 stars is a hot mess

I cant work out how to make this nice. Maye a circle layout can do it. 


52 Stars looks better 


60 stars









Friday, May 02, 2025

Let's make Bee honeycomb more natural

Honeycombs in nature are not entirely regular. In a 2016 study, Nazzi found that cell size variation in honeycomb averaged just 2.1%, with standard deviation across samples of ±0.6%. This highlights how remarkably consistent bees are — yet not perfectly so.

A little irregularity might actually help bees, by making the environment less predictable for their enemies

  • Mites might find entirely regular honeycombs easier to deal with
  • Entirely regular honeycombs might produce bees with less variety in sizes
    • This might make it easier for predators and parasites to specialise given less variance in the bees
    • It might slightly reduce the variety of foods bees eat


When we manage hives, we often insert wax foundation sheets embossed with perfect hexagons to guide the bees' construction. But maybe we shouldn’t.
Maybe our foundation should closely match the natural variation bees already produce. It might be a small change — but one that works with evolution, not against it.

Here’s the code I used to simulate a naturally varied honeycomb layout.




import numpy as np
import matplotlib.pyplot as plt
from scipy.spatial import Voronoi
from shapely.geometry import Polygon, Point

def generate_jittered_hex_points(rows, cols, spacing=1.0, jitter=0.05):
"""Generate a grid of points in a hexagonal layout with jitter applied."""
points = []
h = np.sqrt(3) * spacing / 2 # vertical distance between rows
for row in range(rows):
for col in range(cols):
x = col * 1.5 * spacing
y = row * h * 2 + (h if col % 2 else 0)
# Add jitter
x += np.random.uniform(-jitter, jitter) * spacing
y += np.random.uniform(-jitter, jitter) * spacing
points.append((x, y))
return np.array(points)

def filtered_voronoi_polygons(vor, points, margin):
"""Return only Voronoi regions that are within the central margin area."""
regions = []
valid_polygon_centers = []
center_x = (np.max(points[:, 0]) + np.min(points[:, 0])) / 2
center_y = (np.max(points[:, 1]) + np.min(points[:, 1])) / 2
width = np.max(points[:, 0]) - np.min(points[:, 0])
height = np.max(points[:, 1]) - np.min(points[:, 1])

allowed_box = Polygon([
(center_x - width/2 + margin, center_y - height/2 + margin),
(center_x - width/2 + margin, center_y + height/2 - margin),
(center_x + width/2 - margin, center_y + height/2 - margin),
(center_x + width/2 - margin, center_y - height/2 + margin),
])

for point_idx, region_index in enumerate(vor.point_region):
region = vor.regions[region_index]
if not region or -1 in region:
continue
polygon = Polygon([vor.vertices[i] for i in region])
if allowed_box.contains(Point(points[point_idx])):
regions.append(polygon)
valid_polygon_centers.append(points[point_idx])
return regions

# Parameters
rows, cols = 20, 20
spacing = 1.0
jitter = 0.042 # to get an average of 2.1% jitter
points = generate_jittered_hex_points(rows, cols, spacing, jitter)

# Voronoi diagram
vor = Voronoi(points)

# Margin (in same units as spacing)
margin = spacing * 1.0 # Leave one cell of wax space around

# Get filtered polygons
filtered_polygons = filtered_voronoi_polygons(vor, points, margin)

# Plotting
fig, ax = plt.subplots(figsize=(10, 10))
ax.set_aspect('equal')
ax.axis('off')

for poly in filtered_polygons:
x, y = poly.exterior.xy
ax.plot(x, y, color='black', linewidth=0.5)

plt.savefig("jittered_voronoi_clean_edges.png", dpi=300, bbox_inches='tight', pad_inches=0)
plt.close()


As well as encouraging natural variation in cell size, I would also like to see foundation sheets reflect the natural tilt of honeycomb cells.
Bees build each cell with a slight upward slope, typically between 9 and 13 degrees, averaging around 9°

While bees in managed hives do seem to recreate this slope reliably on their own, adding a subtly varied tilt to the foundation embossing rather than a perfectly uniform angle. Mind you, since bees usually reproduce this slope, sloped embossing is likely less useful than capturing variation in cell size.

There's also a theory that a small number of undersized cells in the comb may help control Varroa mites. The idea is that bees raised in smaller cells hatch slightly earlier, disrupting the mites' reproductive cycle. While results from studies are mixed to negative, it's another reason to consider embracing natural variation, rather than enforcing a rigid cell size across the hive.