EnergySage News

https://news.energysage.com/longevity-of-solar/ : 0.7 percent degradation per year. That works out at over 80% after 25 years. The inverters need slightly more frequent replacement. The compounding effects on this are going to be dramatic. Everyone who borrowed money at sub-5% rates and then saw retail electricity going up by 50% made a great decision.

I imagine many are. But in small spaces with poor ventilation (e.g. vehicle interiors) that might not be enough. The sealed batteries still have a vent for the gas to leak (in a controlled manner). https://electronics.stackexchange.com/questions/175649/are-sealed-lead… But besides that, li-ion batteries have more energy per weight, are more efficient at storing energy, and can be discharged to a farther level without negatively impacting the battery. Sorry for the annoying popups, this is the best source I could find: https://news.energysage.com/lithium-ion-vs-lead-acid-batteries/

California has started requiring rooftop solar on new home builds (with a few exceptions): https://news.energysage.com/an-overview-of-the-california-solar-mandat… I'm not sure it is a great idea. Utility scale solar farms are more cost effective and California has plenty of room for more solar farms, even though the farm approach requires more transmission investments. It might prove beneficial if PG&E continues to respond to high fire risk conditions by shutting off power delivery.

Um fusion being close to being viable, which your link is supporting, doesn't mean it's close enough to help us this century with regarding climate change (which is what your link is about), which isn't what I said it would do. I apologize if I worded it a way that you felt implied that. South Korea I understand is investing heavily here[1]. If I'm not mistaken so is China. Too bad we (Western society) can't work with Iran on this as well. However, please consider when we talk about changing our sources of energy over, that what will work has to work within costs and regulatory conditions. If I'm not mistaken it can take around 20 years for an experienced nuclear capable nation to get a reactor up and running from initial phase of saying yes you can build a reactor. Solar is outpacing that.[2] Which your link also supports. "The pattern of power supply is changing. The massive take-up of solar power by households means we have now permanently shifted from the old model of large power stations to one where supply is distributed around the network. " Fission (by itself) is not solving climate change this century either. Additionally I think fission powered cargo ships would be a great option to reduce carbon emissions too. Since the U.S. Navy is very experienced with nuclear powered vessels and Russia has that nuclear powered icebreaker, I think it's technology possible. Unfortunately setting up a regularity system for that is likely completely unrealistic though I'm…

I've just run my own numbers. But looking at your image, something seems seriously seriously off on the solar side. I get roughly similar numbers for nuclear; e.g. 250 thousand metric tonnes concrete / TWh for an AP1000 and 5x that for Sizewell B, using concrete mass numbers from [0]. Averaging these two designs is really close to their 760 number for concrete. For solar, let's take some average random numbers, 800 pounds for a 6kW array on a roof [1]. So starting just with the panels, a 25% capacity factor over 30 years will generate 394 MWh == 0.000394 TWh. 800 pounds is 0.000363 thousand metric tonnes. So converting to the units of thousand metric tonnes / TWh, we are at 900 thousand metric tonnes/TWh for the panels for solar. Add another 10% for inverters, double that for framing if you're installing in a field rather than on a house, and I don't know where they are coming up with their stuff. 2700 tonnes/GWh for glass alone is ludicrous. I'm not sure where that report comes from, but it would be worth checking the sources. After a basic sniff test, I'm going to dismiss it. Maybe it's using weights from 1980 solar panels or something. [0] https://web.archive.org/web/20110722031413/http://www.nuclearinst.com/… [1] https://news.energysage.com/average-solar-panel-size-weight/ Edit: and honestly, both weight / Wh and land / Wh are fairly meaningless numbers for both technologies. What…

There's always the opinion that solar is useless on cloudy days. It's my understanding that on a normal cloudy day they're only 25% as efficient as when sunny, and 10% when it's really cloudy. So, not great, but it's something that is being improved upon all the time. > In some cases, clouds can actually result in better panel performance than standard sunny weather. A cloud can reflect or sometimes even magnify sunlight, which results in additional power output from your solar panels. [0] In my country (Oz) we have two states that are into solar: SA has a tesla battery plant (built in <100 days) [1], but more as a 'surge saver', and WA which has recently mentioned it's about to reach serious trouble because solar is now getting in the way of it's existing non-renewable coal (meaning there's an over supply). WA doesn't have battery storage up and running, whereas in SA the tesla plant can ramp up demand almost instantaneously and is saving a bucket load of cash per year (because the coal plants don't need to spin up another turbine to meet demand: something which takes hours to achieve AND is costly) > "We know that the 100 megawatt capacity of the existing Hornsdale battery has saved South Australian electricity consumers $40 million per year since its inception," he said. [1] [0] https://news.energysage.com/solar-panels-work-night-cloudy-day/ [1] https://www.abc.net.au/news/2019-11-19/sa-big-battery-set-to-get-even-… In short, the good thing about solar…

It's tougher than that. They are outdoors and have to stand up to weathering and storms. In the case of dual axis trackers they have an additional degree of freedom. Finally, an the toughest, in my opinion, is how little net energy budget they have to work with to be economical: they have to require less energy to build, install, and operate than the incremental solar energy they generate over their operation life. They give an approximately 40% production improvement (that's roughly the single/dual axis midpoint. towards the high side), so if you say a 10 yr life with zero maintenance and controlling a single 250w panel you're talking 9 mWh, or $1080 retail electricity value generated. A 40% improvement on that is only $440 worth of energy budget per tracker over a 10 year life. That glosses over a ton of complexity like if area is amenable to ground vs rooftop, if it's higher latitude, high density panels, stationary panel/tracking mirror, and most importantly having multiple panels per tracker. Zero maintenance/replacement is not realistic, either, since it would cycling dozens of times a day and could be in hurricane/tornado areas. But given a lower end garage door opener is $150 before installation costs, it gives an idea how tough that would in that price range. Consider that panels are generally engineered to withstand 100+ mph gusts, and this would be a relatively finely tuned machine attached to one or more 18 square foot kites that would be expected to withstand…

As long as they have rapid shutdown and the ports are built into a manner without a suicide cable, I suppose so? https://news.energysage.com/rapid-shutdown-overview/ https://en.wiktionary.org/wiki/suicide_cable

It says they get 300kW per 20-ft container. This says the average house (U.S.) uses about 30kW in a day. So that gets about 10 homes per container. https://news.energysage.com/how-many-watts-does-it-take-to-run-a-house…

depends on time of day and local electricity rates. most of your charging will be at home which is much cheaper than supercharges. >In general, the cost of charging a Tesla is more than 3 times cheaper per mile than the cost of fueling a gas-powered car (4.56 cents per mile compared to approximately 13.73 cents per mile for gas vehicles). from: https://news.energysage.com/tesla-charging-cost-vs-gas/ a different take: >It depends on what you are comparing it to gas wise. In my area, approximate numbers are 11 cents a kWh at home, 28 cent at a SC. I will get roughly 3 miles to the kWh so a mile costs me 9 cents if I SC. Gas is $3.30 a gallon so my car would need to get 36 miles to the gallon or better to compete with SC'ing. from: https://www.reddit.com/r/TeslaModel3/comments/stbpfb/comment/hx2uws8/?…

A desktop computer uses about $20 a year of electricity, so this seems fine. https://news.energysage.com/how-many-watts-does-a-computer-use Let's get rid of television.

> If it's the latter, then reduction of 1 kWh delivered should save them the same amount of money. The "net metering" policy being changed isn't regarding "saving the grid the money by reducing the amount delivered to a customer." If you don't use the power from them, you don't pay for it. But this is about the utility paying the customer the retail rate for excess generation - aka paying retail rate for something that would offset a cost they'd otherwise pay wholesale rate to generate. This is about the current (not the new) system: https://news.energysage.com/net-metering-2-0-in-california-everything-… It's not clear to me at all that it makes sense to compel the utility to purchase your excess power at the retail rate, if you're generating more than you can use. It also seems to gives weird incentives to size and spend on your home setup.

Googling shows gains of 25-35%. Dual tracking adds another 5-10%. I can really see how just placing more of these simple flat ones would be more economical than a complicated racking and tracking system. https://news.energysage.com/solar-trackers-everything-need-know/

which limits power to around 1100W All those 1800+ watt hair dryers that are used very commonly in the U.S. are wondering where you got your wattage limit from. https://news.energysage.com/how-many-watts-does-a-hair-dryer-use/

Perhaps lead is not so environmentally friendly? Here [1] are some of the reasons li-ion is currently preferred. This will change with time. I am holding out for the 3D printed solid state batteries which are not mentioned on that page but soon to be in mass production. [1] - https://news.energysage.com/lithium-ion-vs-lead-acid-batteries/

> I'm not talking about things like circuit breakers or child-safing banisters and railings For example, in California, all new homes must have solar power, with the requirement that [1]: > The solar panel system needs to be large enough to meet the annual electricity usage of the building > builders can decrease the size requirement of a system on a property by incorporating battery storage ... <and> ... by incorporating energy efficiency measures or other demand-responsive measures 1. https://news.energysage.com/an-overview-of-the-california-solar-mandat…

Here's some progression of panel efficiency over time: https://news.energysage.com/solar-panel-efficiency-cost-over-time/ I would suggest it's a matter of "nothing changes in a year but everything changes in a decade." Partial apologies for the tone; I'm personally kinda sick of Internet comments crapping on people's work by default.

It took time to find a pro-solar source which touched upon the subject (other were Forbes and shady websites): https://news.energysage.com/solar-panels-toxic-environment/ Basically, what i've heard before (i only skimmed the source), all solar panel are toxic, because the production create use a lot of chemical and create byproducts. We ignore this, it mostly hit poor areas in China and Africa, and this pollution will disapear in less than a century. The end-of-life is OK for old-style PV. Most "new" type of solar panels however, especially those you put on your own roof, are extremely toxic at their end-of-life, and what's worse is that their toxicity are not due to a chemical compound but to elements. What's even worse is that those elements are heavy metals, so bury even one of those PV panels in the ground and it become cancer-land a few year after.

Hmm, seems weird that the price per watt doesn’t seem to have dropped since then, unless we got a really good deal..? https://news.energysage.com/how-much-does-the-average-solar-panel-inst…

That would be an awesome price even if it's after the federal tax credit. Here's a link to average prices by system size, that's way under even for the smaller size. https://news.energysage.com/how-much-does-the-average-solar-panel-inst… Also rooftop solar is 2-3x the cost of utility scale solar.

How is that different than 8 kw of solar panels in a utility scale solar installation that costs significantly less than your residential system? $0.94/W for utility scale [1], and $2.81/W for residential [2]. 1. https://www.greentechmedia.com/articles/read/key-2020-us-solar-pv-cost… 2. https://news.energysage.com/how-much-does-the-average-solar-panel-inst…

Hi HN! Time-of-use and "demand charge" power pricing systems [1] mean that utilities in the US are starting to price their electricity dynamically though the day. It gets expensive at 4-9p when everyone wants to run their AC in summer, but is cheap in the early mornings. Problem: The times and prices change by weekday, season, and utility. Solution: A Chrome extension that shows you the current status, and whether to use / not to use. Starting with two utilities in California - PG&E [2] and SCE [3]. [1] https://news.energysage.com/understanding-time-of-use-rates [2] PGE: https://www.pge.com/en_US/residential/rate-plans/rate-plan-options/tim… [3] SCE: https://www.sce.com/residential/rates/Time-Of-Use-Residential-Rate-Pla…

According to this site (https://news.energysage.com/tesla-solar-roof-price-vs-solar-panels/) it is not only ~33% more expensive but also less efficient.

Needs 7-9 panels approx 5ft x 3ft. A roof array might work but a backyard is ambitious unless you're on flat land and facing south west https://news.energysage.com/how-many-panels-do-you-need-for-your-ev/

Don't die in the next 20 years, and you're going to see it for yourself: https://news.energysage.com/states-with-100-renewable-targets/ It's not really that hard. Build a lot of wind turbines (more than 100% coverage), reinforce the grid and add some storage. Offshore wind turbines is a thing. The tech is still somewhat in its infancy, but the costs are coming down. For a high bound regarding storage, take hydrogen, otherwise whatever cheaper will be in production when you get to it. There are several academic studies of this. It's not rocket science, just lots of incremental engineering and economics of scale. If your point is that cities don't have space to provide their own power, yes, you're right, just as they don't have space to grow their own food.

https://news.energysage.com/shopping-solar-panels-pay-attention-to-sol… You're right. 4 on this list have 25 year warranties... but the rest.. ouch.

Depends on the manufacturer, by the looks of it: https://news.energysage.com/how-long-do-solar-panels-last/ .3%/year would be 85% after 50 years, so I was off by a bit.

It's like any sort of tech: the first version is too expensive and then the price drops some % every year until we all have "supercomputers" in our pockets. Plain Solar Panel (non roof) installation has gone from $52k to $20k in the last decade [1] which is craziness. The other aspect of this is longevity. Setting all solar power generation aspects aside an asphalt roof will generally last 20-25 years. Tesla roof tiles appear to last much longer (infinite warranty, etc.) and are maybe more comparable to a slate roof which would be 10x the cost of an asphalt roof. As a reference point, I grew up in a house built in the 1920s and just confirmed via Google Streetview that it still has it's original slate roof. 1 - https://news.energysage.com/solar-panel-efficiency-cost-over-time/

Under a rare bipartisan deal at the end of last year, the solar investment tax credit remains at 30% through the end of 2019, then declines to 26% and 22% in 2020 and 2021 respectively. After that, there's no investment tax credit for residential solar. http://news.energysage.com/congress-extends-the-solar-tax-credit/

Monocrystalline Si solar panels have so many advantages that it's hard to get interested in anything else for home or business construction. Lifetime is measured in decades, not years; efficiency is approaching 25% while prices are dropping (only expensive multi-junction III-V types are better, currently limited to satellite power systems); and for variable surfaces, they can be manufactured as small shingles as well as the standard size panel. Unfortunately the USA, due to decades of minimal R&D funding, is well behind the technology curve in this area: > "Some Chinese companies are defying the “more efficient = more expensive” rule in 2022. High efficiency solar panels are entering the market from companies like LonGi, Canadian Solar, and Trina Solar that surpass the 20 percent efficiency rating, but cost less per watt as opposed to SunPower, LG and Panasonic panels. Solar is cheaper than ever without sacrificing efficiency ratings, which begs the question if U.S manufacturers will be able to maintain their pricing premiums." https://news.energysage.com/what-are-the-most-efficient-solar-panels-o… Of course a boom in solar PV installation in the USA would pull the rug out from under natural gas prices, which more-or-less explains government policy in this area.