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Discussion (114 Comments)Read Original on HackerNews
I set it all up myself, and while it is not trivial, it's not difficult either.
Learning to put connectors on properly, size cables and put lugs on properly, learn about earthing and breakers...just one bit at a time.
I'm about to set up another system on the roof of an outbuilding to supply power for a water pump and irrigation where we grow food. This will be much easier and simpler since it will have only one 48V lithium battery, but I'll still use Victron stuff and connect it to a Cerbo so it can be monitored.
If I sold this place and bought somewhere on the grid, the first thing I'd do is cut the cord and set up my own system again.
I know in florida you have janky laws stopping you, but below 10kw it's still relatively easy.
I have a friend who installed <10kw of solar panels and they're now 97% off-grid in hot, wet florida weather with an old low-seer AC, single-pane windows and poor roof insulation which is roughly 60% of the energy usage.
The reason they got it is actually not to save money or anything, but to have power when grid goes down after hurricanes.
A landowner wanted to run power to their land, they got quoted 100k and possibly 250k to run less than 2 miles of powerlines.
The land owner fired back with the question of installing solar panels instead as it would be cheaper and free.
The representitive replied with: "Look around you, there's no solar panels because they don't work."
Less than 100k later, the landowner had full off-grid power via solar and a backup generator.
I guess at the end of the day they saw all the sunshine around them and said: "You're right, all that sun is mine and mine alone."
I think it would if it was indeed “essentially free”. Rooftop solar is unfortunately a racket though, and companies price-gouge like crazy and also collude to keep prices inflated.
But the very idea of not being dependent on the grid or fossil fuels, if one can afford it and costs are comparable, should sell itself.
But my dad watches Fox News so he brings up lies like how bad wind turbines are for the environment (coal anyone?) or how we shouldn't make ourselves dependent on China for solar (as if we aren't dependent on a lot of bad hombres for our current energy mix or as if receiving solar makes us dependent at all).
For a place that was two miles from a power line, I would think anyone would approve of off-grid.
There is a limit to the size of the instantaneous increases and decreases in generation that the other generators on the grid can compensate for
I looked at using an AIO for my PC build but ultimately went with an air cooler the size of a damned rubix cube and a high airflow case.
My room gets toasty with raytracing titles, lol
source: my 9950X, happily running air cooled.
(Embarrassingly, I have an M4 Max that can almost match it in the CPU-bound workload I care about while sipping some 45W. The rest of the industry really needs to catch up with Apple on power efficiency.)
Though I can totally understand, geeky people love details. I have a habit of getting way too detailed in my writings here. So I then spend most of the time editing it down to be as clear and brief as possible. I refuse to use an LLM for my own thoughts.
Probably a better choice as an appendix, move the good stuff up to the top. But overall its NBD.
Most people drive cars worth less than this.
You still need a few terabytes to enter the real cars territory.
I really have to wonder if people truly know how powerful any modern computer is. Like I just assume any modern PC with sufficient storage can handle a database with a billion rows of data. I think my phone probably could.
Now if you were, say, analyzing commercial satellite imagery of the entire US and trying to find rooftop solar, matching it against the database and finding data that wasn't in the dataset, that's something where your computer power would be way more relevant.
Come to think of it, you could probably use such imagery to construct a power generation network from power plants to transmission lines to utility poles. Of course some places have underground cables but there are other datasets for that.
Another interesting project is mapping the growth of solar. This would require access to commercial satellite imagery over time. I'm sure some government agency already does it. Or used to at least. Snapshots years or even months apart are less interesting.
Anyway, I guess the point is the author's computer is capable of way more than I suspect they think it is.
Because he wants to tell you about his computer it means he doesn’t know how capable it is?
In my native Netherlands I'd guess to see that peaking at ~south at say 15-30 degrees, with some lower peaks at east/west combos.
Curious to see what it would be in this dataset.
Folks are doing some interesting exploration of the pros and cons of different alignments, e.g.:
> When roof area is limited, the question becomes: What layout lets you install the most space-efficient solar capacity within budget on the available area? In those scenarios, an east–west (E–W) layout can outperform a south-facing layout. The South layout may be “better positioned”, but the E-W allows the installation of more panels in the same area.
* https://ases.org/east-west-vs-south-facing-solar-when-more-p...
Basically examining 'quality versus quantity', depending on what your location and roof allows.
I installed a east/west facing set myself on our flat roof. Looking at dynamic power prices of the preceding year, multiplied by expected power output. Even wrote a simple space optimizer for this one time. But messed up some measurements so had to change on the fly anyways. The old adagium still holds: measure once and curse twice.
https://ratedpower.com/blog/solar-panel-orientation/
Seems to match my experience as well, I got a set of 12 south facing panels and a set of 12 split over east and west on my flat roof. The E/W start and end a bit before/after the south facing set.
For panels with east/west azimuth, the tilt should correlate with where the sun is at 7-8AM and 17-18PM, at least in my area.
((I think you have your concept of azimuth and tilt mixed up; I know I have when I was originally typing a different parent comment)
The CSS styles seem to dynamically unload and reload while I’m reading it causing the margins to jump and the fonts change, I’ve never seen anything like this before. FWIW I’m on iOS using brave.
It would be cool to modify them to be per-capita, although I imagine adjusting arbitrary hexes for population density would be a real challenge.
For that matter, I'd be interested in details of how "a team of researchers including alumni from NOAA, NASA and the USGS" (from the previous article) actually collected the data.
https://www.nature.com/articles/s41597-025-05862-4
In the abstract: “We use these newly compiled and delineated solar arrays and panel-rows to harmonize and independently estimate value-added attributes to existing datasets including installation year, azimuth, mount technology, panel-row area and dimensions, inter-row spacing, ground cover ratio, tilt, and installed capacity.“
Still, an order of magnitude less new capacity than China - but not two orders.
It’s OK to celebrate small wins. The US doesn’t have to be #1 in everything. We also seem to have a curious diseconomy of scale on mega infrastructure projects for complex reasons, so maybe slow growth is the right approach.
Energy heavy use cases with little to no energy costs will lap western industries.
In order to keep growing, the US power grid is going to need big, coordinated projects. Solar, wind, transmission lines, and batteries.
I think with political interest from Dems who like renewables, and big business who need energy, there's will in the US to do it, but of course it's the US, so we'll do the right thing after every possible alternative has been exhausted.
In many ways this mirrors the way America walked into the housing crisis with its eyes closed.
https://en.wikipedia.org/wiki/Ivanpah_Solar_Power_Facility
Solar thermal can't really compete economically with photovoltaics.
https://www.aliexpress.us/item/3256809986804138.html
I'm old enough to remember Carter putting them on WhiteHouse roof and they were thousands of dollars then (and less efficient)
Prices fell dramatically in the last few years, if I understood things correctly the high prices in the US are mostly due to tariffs.
https://www.washingtonpost.com/dc-md-va/2023/03/22/jiimmy-ca...
>It was pretty symbolic back in 1979, too. The symbolism depended on what you thought of Carter and his policies. For some, the panels were a much-needed acknowledgment that America had to wean itself from fossil fuel, explore alternative energy sources and help save the planet. For others, they were in the same category as Carter’s virtue-signaling cardigan. Of course, critics moaned, Carter would put solar panels on the White House.
>The panels came down in 1986 when the White House roof was undergoing repairs. Ronald Reagan did not have them replaced. Of course, Reagan wouldn’t put solar panels on the White House.
What is the story behind Reagan taking down the solar panels installed by Carter? Was it symbolic of a new, less enthusiastic approach to clean energy?
https://www.reddit.com/r/AskHistorians/comments/g4w4ww/what_...
Solar power at the White House
https://en.wikipedia.org/wiki/Solar_power_at_the_White_House
>On June 20, 1979, 32 solar water heating panels were placed on the roof of the West Wing. The panels were made by InterTechnology/Solar Corp. from Warrenton, Virginia and installed by Hector Guevara of Alternate Energy Industries Corp.[2] At the dedication ceremony for the panels, President Carter said, "In the year 2000 this solar water heater behind me, which is being dedicated today, will still be here supplying cheap, efficient energy... A generation from now, this solar heater can either be a curiosity, a museum piece, an example of a road not taken or it can be just a small part of one of the greatest and most exciting adventures ever undertaken by the American people".[1]
The whole installation cost $35,000 in 1979 (about $160,000 now).
https://books.google.nl/books?id=e9dlzwL4Ck4C&dq=solar+white...
Also the panels Carter installed were solar water heaters - in 1979 solar photovoltaics were just starting to expand beyond satellites and cost like $40/watt.
and if you buy 2 at a time there are multiple 10% codes available
so it's $67 USD for 200watts
100watt 18volt 5amp panels that can be put in series or parallel
for $33 each, it's crazy
I bought 30 375w Canadian Solar panels 2 years ago and paid $0.41/watt (~$4536 for the whole package)
My mounting equipment actually cost more than the panels (~$4600). And the permitting process cost nearly as much as the panels (permit cost + architectural drawing + structural engineer stamp + electrician stamp).
It's crazy how cheap solar panels themselves are getting. They're going to win on the energy front - period. Especially now that battery tech actually seems to be moving again. I vividly remember one of my robotics professors in undergrad ranting about how frustrated he was with battery tech in ~2007, but LFP and sodium batteries are both pretty huge steps forward.
https://images2.imgbox.com/8b/e1/R6pnQUCr_o.jpg