Solar PV panels are as cheap as plywood at this point (sometimes cheaper, depends on your market as always). The cost is mostly soft costs (permitting, etc), labor, and the frame. Rooftop residential solar is still 3x-5x more expensive than ground mount, commercial is somewhere in between due to scale. Ground mount total cost is ~$1/watt, residential solar ~$3-5/watt.
Easiest wins are code to require large commercial and industrial buildings to meet load requirements for future solar installs, parking lot canopies that are solar ready (or solar installed at time of canopy install), and in the case of residential, ground mount with low regulatory overhead and minimal to no shading.
> Rooftop residential solar is still 3x-5x more expensive than ground mount
which is puzzling to me, because most feasible rooftop solar needs close to zero prep work to be able to mount the panels on the roof. Ground mount needs either helical screws or concrete footings, both of which are relatively expensive in terms of either material and/or labor/time.
You need a scaffold, which costs. The roof must be able to hold the additional mass (can be problematic in older buildings), you have to remove tiles and attach supports to the rafters and properly close the roof again. Sure, it's quick once work starts, but there's still some investment in material and tools you don't need on the ground.
Wow US prices are high.
Putting solar on an existing brick/concrete wall (as essentially cladding) costs about 20ct/W here in Germany; bifacial fence rows should be slightly higher; a mini excavator should be pretty quick at sinking the posts into the ground.
Land cost is immaterial when talking utility scale ground mount and rooftop. Grid connection improvement costs are highly variable and dependent on local distribution infra. Solar is so cheap, you can usually roll the generator development cost component into the financing, with the utility paying the other component of it.
> The kW per acre metric is pretty poor for solar, especially when you get out of sunny desert areas.
The data says different. Broadly speaking, anywhere in the continental US is favorable for solar. The US gets more sunlight than Germany, and Germany has 101GW of solar capacity installed as of this comment (deploying ~2GW/month). You might need more panels near Canada, but panels and land are cheap, and demand for power is low due to limited population (caveats being PNW, served by hydro, and NE-ISO in New England, which is going to turn up a transmission line in December to bring 1.2GW of hydro from Québec).
For comparison, the US ag industry farms almost 60 million acres for soybean and corn biofuel, and that is far less cost and resource efficient than covering that land in solar PV.
This is true, but a bit of a dodge. Solar is competing with gas, so when you have a land parcel and want to maximize the energy you get from it, you need lots of sunshine to beat out gas.
This also factors heavily into where we use energy vs. where we produce it, and the associated losses. You can slot a GW of gas generation into ~350 acres anywhere. Solar you need ~5,000 acres with lots of sun. Combine this with the fact that the land where energy is used (population centers) is the land that is most expensive, and the difference becomes substantial. This also doesn't factor in energy storage costs, which is also necessary to reach parity with gas.
Also, don't take this as me attacking solar, I am a huge proponent, but there is a reality check needed so people can understand why we aren't paving the earth with panels despite constant headlines of "Solar is the cheapest energy". It's the cheapest energy when in an ideal location, and overwhelming majority of people in the US don't live in an ideal location.
This however doesn't really apply to non-gridscale generation. People can (and should) put panels on their roofs and batteries in their basement.
We sort of are paving the earth with panels, depending on your definition of “we”. Globally we installed 380GW nameplate just in the first half of this year and will probably match that in the second half.
Gas generation manufacturing has a 7-10 year backlog [1] [2]. You can build ~1GW of solar in under a year [3] (1GW of solar is deployed every 15 hours globally, as of this comment, tangentially). As you can see with Intermountain in Utah, supplying power to Los Angeles (via Path 27), you can site batteries and renewables in the middle of nowhere and leverage existing transmission to get utility scale solar to load centers [4]. Again, there is lots of land everywhere, and it is straightforward to get solar generated to the load. It doesn't matter that solar takes more land than gas, nuclear, or other legacy generator technologies; its cost makes it a non issue. Also, solar, backed by battery storage, is cheaper than gas in most cases [5] [6] [7] [8].
No dodge, solar won, and it is going to steamroll fossil fuels globally as battery storage deployment comes up to speed [9] [10].
> To call solar power’s rise exponential is not hyperbole, but a statement of fact. Installed solar capacity doubles roughly every three years, and so grows ten-fold each decade. Such sustained growth is seldom seen in anything that matters. That makes it hard for people to get their heads round what is going on. When it was a tenth of its current size ten years ago, solar power was still seen as marginal even by experts who knew how fast it had grown. The next ten-fold increase will be equivalent to multiplying the world’s entire fleet of nuclear reactors by eight in less than the time it typically takes to build just a single one of them.
> Solar cells will in all likelihood be the single biggest source of electrical power on the planet by the mid 2030s. By the 2040s they may be the largest source not just of electricity but of all energy. On current trends, the all-in cost of the electricity they produce promises to be less than half as expensive as the cheapest available today. This will not stop climate change, but could slow it a lot faster. Much of the world—including Africa, where 600m people still cannot light their homes—will begin to feel energy-rich. That feeling will be a new and transformational one for humankind.
The fact that there is a back log of gas turbines when there is an excess of solar panels should make my point clear, and explain to people why there is a backlog when solar is so cheap and readily available...
I think you misunderstand. The backlog is not due to wild demand for gas turbines; it is due to structural supply chain and labor constraints around building gas turbines. The backlog means there is only so much gas turbine capacity that can get built; if there is any hiccup in the supply chain, it will further destroy the ability to deploy gas, forcing more rapid renewables and storage uptake. That gas manufacturing also has to compete against demand destruction as renewables and storage keep getting cheaper.
So, when you say "well, they'll just build gas turbines instead," (in your comment I replied to) they cannot. There is no capacity, and no desire to increase capacity. They can barely build them already, and it would be pretty easy to make it harder to build them by finding points of fail to force to failure in their supply and labor chains. Smart money isn't going to invest in a technology that, from all indications, doesn't have longevity based on competing technologies. Existing gas turbine manufacturing is squeezing out the last of economic gains available before the industry shrinks further.
> US financial markets are favoring renewable energy over fossil fuels, with global investment for new renewable energy development reaching a record $386 billion during the first half of 2025.
> Revenue forecasts show a widening dichotomy between clean and dirty industries, with renewables expected to report 16% sales growth next year and 21% in 2027, while traditional energy companies report 1% and 6% sales growth.
> Global renewable power is forecast to increase by 4,600 gigawatts by the end of the decade, an amount equivalent to adding the generation capacity of China, the EU and Japan.
> Even as the US and European Union recently increased their reliance on coal, solar dethroned the fossil fuel mainstay last year, becoming the world’s most installed energy generation technology according to BloombergNEF’s 2025 Power Transition Trends report. “In 2015, solar power seemed far from overtaking coal, constrained both by scale and economics,” BloombergNEF said in report this month. Yet, within a decade, solar costs have fallen so dramatically that the dynamic has entirely reversed. Solar is now two times cheaper than the fossil fuel.” So-called green energy is the lowest-cost and quickest-to-deploy power generator in the US, even without incentives, according to Lazard Inc.
“The large changes within the planned power capacity mix highlight the impact of the sudden swing in federal government energy policies following the reelection of U.S. President Donald Trump.” Globally renewables are absolutely dominant. Even the changes in the US are taking us from 7%/74% new to something still pretty lopsided.
Easiest wins are code to require large commercial and industrial buildings to meet load requirements for future solar installs, parking lot canopies that are solar ready (or solar installed at time of canopy install), and in the case of residential, ground mount with low regulatory overhead and minimal to no shading.
Related:
NREL: Solar Installed System Cost Analysis - https://www.nrel.gov/solar/market-research-analysis/solar-in...
Cheap DIY solar fence design - https://news.ycombinator.com/item?id=45597198 - October 2025
Great comment from that thread on cost breakdown (Alaska): https://news.ycombinator.com/item?id=45692595