The irony is that the distribution company in my state has been privatised and the QoS has nosedived. People are looking for backups and by far the fastest and easiest solution is to buy a diesel powered generator (which doesn't have the same emissions/noise requirements as cars).
There is visible growth in solar, but you see it more often in businesses, because the return on investment takes a long time for a house (10-15 years).
For roof top solar? Can you give an example of some numbers? Around here in NorCal, would cost ~20k for a system, and would save maybe $2400 a year, so would be more like 8.3 years.
US residential rooftop is wildly expensive compared to other countries due to soft costs ($3-$4/watt vs $1-2). California’s “unique” electric utility and solar policy approach doesn’t help.
I put solar on a friend’s roof in Sydney Australia (their landlord’s specifically, due to a lease to purchase agreement) for under $1/watt.
I have noticed this! But I dont get it. Construction labour in the US is generally much cheaper than in australia. In fact almost everything is cheaper in the US. Why is solar so much more expensive? whats in those "soft costs"?
In short: bureaucracy. Depends on state but electrical things and stuff attached to houses usually requires greasing the local municipality with permits, submitting a plan, and hiring licensed electricians that cost way more than a general contractor. It may even require presenting it for approval to a HOA or town committee (god forbid the house might be historic, then it's another committee)
EDIT: My parents looked into it in NJ awhile back but their land is farm preserved and it's super restrictive on how much they can cover with a 'solar farm'. Also, it requires studies that prove it won't cast shadows or reflect onto neighboring properties. The township is extremely restrictive on what can be built anywhere (for example the center parts of it are mostly a deadzone for cellphones since the towers must only be installed on the border of the township).
Import regulations means Chinese equipment that you buy is a bit more expensive. The domestically produced stuff is not cheaper or better or that widely available.
The rest is just a mix of bureaucracy, regulations, building codes, energy companies frustrating the whole process, etc.
An additional factor is latitude. In Australia places like Sydney and Brisbane, are a lot closer to the equator than most of the US. San Diego is about comparable (well slightly closer) with Melbourne in how close it is to the equator. So, they'd be getting a bit more out of their panels even in the middle of their winter.
I'm in Germany, most of the country is about ten degrees further north than most of the US. People put solar on their roofs here because it works and there are some incentives. So, it's not that big of a factor. But if you add it all up, the US should be getting its solar a lot cheaper than it currently is.
Part of the problem with batteries (apart from the tech) is that Australia has retreated from trying to get people to pay for their power and are resorting back to subsidy and cross subsidy for political reasons.
Whether or not it’s a good thing is up for debate but it’s certainly harming battery ROI.
I have a total of 23 solar panels with a maximum output of just over 1 MWh/month. The system cost around 34,000 BRL which is around 6,850 USD at current rates. Its expected lifetime is 25 years and it broke even in about three and half years. Current energy prices in USD/kWh varies between 0.15 and 0.17. The panels have been operating for about five years now and capacity has been expanded once already. They have generated a total of around 45 MWh. In 2023 output maxed out in November at 1.072 MWh and bottomed out in June at 396 kWh. The highest output ever recorded was 1.136 MWh in January 2021.
I have no batteries. In Brazil there's no way to go 100% off the grid so I decided against the added maintenance complexity of batteries. Energy is injected directly into the grid in exchange for "kWh credits" which expire in one year if unused. I suppose their aim was to incentivize people to produce as much energy as they consume since it makes no financial sense accumulate surplus credits by producing more. I've considered expanding production capacity anyway and just converting the excess energy into cryptocurrency. They refuse to pay me so I'll just sink any surplus into miners instead of giving it to them for free. Haven't gotten around to actually doing it though.
You're right, sorry. That figure is energy output per month. Edited the post to make that clear. Added some extra statistics too from the monitoring software's report.
Is it possible my idea of "panel" is different from everyone else's? I'm counting the individual units which I purchased and which were installed on my rooftop. I suppose it's possible these units are made up of multiple actual panels, each with the aforementioned 400-500 W capacity. Not sure.
You are mixing up power (W) and energy (J or Wh, simply Watt times hours in you time window of choice) for starters. And I've never seen any other definition of panel other than the unit you buy them by, roughly 1m by 1.6m. That includes industrial installations of hundreds or thousands of panels.
What's the regulatory situation for selling energy back to the grid? Friend of mine 10+ years ago in Porto Alegre opted for solar for water heating only, because there was no mechanism for net metering.
> What's the regulatory situation for selling energy back to the grid?
You don't sell the energy. Well you kind of do, it's just that they don't pay you in real money. They pay you "kWh credits" which are theorized to offset your consumption in the winter months where solar energy production is lowest. The catch? Those credits expire in one year if unused. They do not accumulate.
So brazilians are financially incentivized to produce as much energy as they consume only. Any energy surplus means giving energy away to the power company for free. Since solar energy production is variable, one also needs to be clever with forecasting in order to estimate highs and lows so that they compensate for each other. Make the summers pay for the winters.
I suppose one could simply work around all that regulatory nonsense by not actually generating any credits in the first place. Build a small system that generates less than needed since that still means significant energy cost reductions. Alternatively, increase energy consumption. Air conditioners are god's gift to brazilians but there are only so many you can buy before you run out of rooms to install them in. So that leaves... Converting any surplus energy into cryptocurrency instead of injecting it into the grid. They won't pay us? We'll pay ourselves by mining monero.
Well, it's solar energy. Pretty much as close to being pure heat as it gets. Completely wasted heat at that: before solar panels, all it did was heat up my home. In fact, I have to pay money every single day in order to run air conditioners to keep that heat out because otherwise it gets so hot I have a panic attack. The heat is actually harmful to me.
With solar panels, I get to redirect that useless sun heat into those air conditioners. The result is more money in my wallet. It's perfect.
Even if I were to mine cryptocurrency, it's still pure heat anyway. Sun's shining whether we want it or not. I'd just buy more panels so I can redirect more sun energy into computer chips instead of allowing it to uselessly heat up my backyard. Processors dissipating heat or backyard radiating away heat at night -- what's the difference?
The system asked me for a hostname of sorts when I set it up. I named it "sun monetizer". Makes the sun useful for something. I used to hate the sun with every fiber of my being. Now I monetize it. The next step is realizing that cryptocurrencies make it possible to monetize the sun at industrial scales by serving as energy-to-money converters.
Sun's gonna continue injecting heat into this earth whether we want it or not. Better make the most of it.
A big problem in Brasil is that most residential building are not built to be energy efficient and modern architecture is making this even worse. No isolation on roof and walls, giant glass planes everywhere.
Can thermal isolation help reduce air conditioning costs by keeping the heat out? I asked someone this once and they looked at me like I was insane. I got the impression this is only done in cold climates.
Yes. Even small retrofits like putting thermal isolation under the tiles or in the attic's floor make a sizable difference. I did this in a home I lived in Rio de Janeiro.
If you are thinking about building in brasil, instead of traditional masonry, consider using insulated structural panels, called EPS in brazil.
I friend of mine did a home using this system in Rio de Janeiro where you easily get over 42C (107 F) outside in the summer. It works fantastically.
Energy in Brasil used to be way less expensive, and traditional masonry and concrete construction is not very friendly to insulation unless you do like the germans that have double walls with the insulation in the middle. So, culturally, insulation is kind of an alien concept for a lot of people and even engineers.
Thanks for the tips!! I do want to get a home of my own design constructed in the future. I've been compiling resources on the matter and the information you provided is extremely useful.
> The catch? Those credits expire in one year if unused. They do not accumulate.
That's kinda fucked up. But well, for my friend in the South, where winters are miserably cold and houses have no heating infrastructure, using the accumulated energy credits during the winter is easy. Heck, there are even crypto-mining heaters available these days, so it kinda works best for him I guess?
Most of brazil have a hot climate, so, nightly usage of air-conditioning is high. You don't even need to wait for winter to use those credits. And if you have money to do so, buying an electric car can be also a good usage of those credits.
> Most of brazil have a hot climate, so, nightly usage of air-conditioning is high.
Yeah. My air conditioners are running pretty much 24/7.
> You don't even need to wait for winter to use those credits.
Depends on how much energy you generate. Solar power can easily generate the amount of energy consumed by air conditioning. Just gotta make sure peak summer output generates enough surplus to cover the needs of the other seasons. My solar system generates between 400-1100 kWh/month. It's always been enough and if my needs change I can always expand capacity.
> And if you have money to do so, buying an electric car can be also a good usage of those credits.
Absolutely. That's my next goal. I don't want to pay for gasoline anymore. I think it's still a bit too early for that, electric cars need to get cheaper for it to be truly worth it.
> the return on investment takes a long time for a house
I completely covered my home's front rooftop with solar panels and they paid for themselves in about three years time. They're so effective that we have politicians campaigning against government incentives for renewable energy. Too many rich people and corporations are benefiting it seems, can't have that.
This is despite the fact that they don't actually pay us for the energy we generate. They give us "kWh credits" which expire if unused after one year. Were it not for that, I'd have even more solar panels in service.
They cannot be sold. They are non-transferable. Best I can do is use it to offset the energy costs of other properties in my name.
Even if they were transferable, I'd probaby get cents on the dollar for them. They expire so they must be worth less than a real kWh. Why would anyone buy these things otherwise? If they were worth the same, people would simply pay their energy bills instead of buying credits from me.
"Brazilian imports of diesel from Russia last year soared 4,600 per cent while purchases of fuel oil rose by almost 400 per cent, in a $8.6bn boost to the Russian economy as the war in Ukraine enters its third year.
Brasília imported 6.1mn tonnes of diesel from Russia in 2023, a 6,000 per cent increase from the 101,000 tonnes the previous year. The value in dollar terms increased 4,600 per cent from $95mn to $4.5bn"
44 comments
[ 2.8 ms ] story [ 98.4 ms ] threadThere is visible growth in solar, but you see it more often in businesses, because the return on investment takes a long time for a house (10-15 years).
In Australia ROI for solar is 3-5 years. Why do you think the discrepancy? Aircon? Grid prices?
https://www.eia.gov/todayinenergy/detail.php?id=56200
I put solar on a friend’s roof in Sydney Australia (their landlord’s specifically, due to a lease to purchase agreement) for under $1/watt.
In short: bureaucracy. Depends on state but electrical things and stuff attached to houses usually requires greasing the local municipality with permits, submitting a plan, and hiring licensed electricians that cost way more than a general contractor. It may even require presenting it for approval to a HOA or town committee (god forbid the house might be historic, then it's another committee)
EDIT: My parents looked into it in NJ awhile back but their land is farm preserved and it's super restrictive on how much they can cover with a 'solar farm'. Also, it requires studies that prove it won't cast shadows or reflect onto neighboring properties. The township is extremely restrictive on what can be built anywhere (for example the center parts of it are mostly a deadzone for cellphones since the towers must only be installed on the border of the township).
The level of bureaucracy in Australia would make most Americans think it a dystopia.
The rest is just a mix of bureaucracy, regulations, building codes, energy companies frustrating the whole process, etc.
An additional factor is latitude. In Australia places like Sydney and Brisbane, are a lot closer to the equator than most of the US. San Diego is about comparable (well slightly closer) with Melbourne in how close it is to the equator. So, they'd be getting a bit more out of their panels even in the middle of their winter.
I'm in Germany, most of the country is about ten degrees further north than most of the US. People put solar on their roofs here because it works and there are some incentives. So, it's not that big of a factor. But if you add it all up, the US should be getting its solar a lot cheaper than it currently is.
Which might have a longer ROI.
Whether or not it’s a good thing is up for debate but it’s certainly harming battery ROI.
Yes.
> Can you give an example of some numbers?
Yes.
I have a total of 23 solar panels with a maximum output of just over 1 MWh/month. The system cost around 34,000 BRL which is around 6,850 USD at current rates. Its expected lifetime is 25 years and it broke even in about three and half years. Current energy prices in USD/kWh varies between 0.15 and 0.17. The panels have been operating for about five years now and capacity has been expanded once already. They have generated a total of around 45 MWh. In 2023 output maxed out in November at 1.072 MWh and bottomed out in June at 396 kWh. The highest output ever recorded was 1.136 MWh in January 2021.
I have no batteries. In Brazil there's no way to go 100% off the grid so I decided against the added maintenance complexity of batteries. Energy is injected directly into the grid in exchange for "kWh credits" which expire in one year if unused. I suppose their aim was to incentivize people to produce as much energy as they consume since it makes no financial sense accumulate surplus credits by producing more. I've considered expanding production capacity anyway and just converting the excess energy into cryptocurrency. They refuse to pay me so I'll just sink any surplus into miners instead of giving it to them for free. Haven't gotten around to actually doing it though.
Panels do 400-500Wp these days. Times 23 gives a max of 11500W peak. You are off somewhere, or tell me right now where you got those panels.
1000000W/mo / 30 day/mo / 24 hr/day = 1388
Is it possible my idea of "panel" is different from everyone else's? I'm counting the individual units which I purchased and which were installed on my rooftop. I suppose it's possible these units are made up of multiple actual panels, each with the aforementioned 400-500 W capacity. Not sure.
You don't sell the energy. Well you kind of do, it's just that they don't pay you in real money. They pay you "kWh credits" which are theorized to offset your consumption in the winter months where solar energy production is lowest. The catch? Those credits expire in one year if unused. They do not accumulate.
So brazilians are financially incentivized to produce as much energy as they consume only. Any energy surplus means giving energy away to the power company for free. Since solar energy production is variable, one also needs to be clever with forecasting in order to estimate highs and lows so that they compensate for each other. Make the summers pay for the winters.
I suppose one could simply work around all that regulatory nonsense by not actually generating any credits in the first place. Build a small system that generates less than needed since that still means significant energy cost reductions. Alternatively, increase energy consumption. Air conditioners are god's gift to brazilians but there are only so many you can buy before you run out of rooms to install them in. So that leaves... Converting any surplus energy into cryptocurrency instead of injecting it into the grid. They won't pay us? We'll pay ourselves by mining monero.
A policy which incentivises turning excess solar energy into one step above pure heat. Classic.
With solar panels, I get to redirect that useless sun heat into those air conditioners. The result is more money in my wallet. It's perfect.
Even if I were to mine cryptocurrency, it's still pure heat anyway. Sun's shining whether we want it or not. I'd just buy more panels so I can redirect more sun energy into computer chips instead of allowing it to uselessly heat up my backyard. Processors dissipating heat or backyard radiating away heat at night -- what's the difference?
The system asked me for a hostname of sorts when I set it up. I named it "sun monetizer". Makes the sun useful for something. I used to hate the sun with every fiber of my being. Now I monetize it. The next step is realizing that cryptocurrencies make it possible to monetize the sun at industrial scales by serving as energy-to-money converters.
Sun's gonna continue injecting heat into this earth whether we want it or not. Better make the most of it.
If you are thinking about building in brasil, instead of traditional masonry, consider using insulated structural panels, called EPS in brazil. I friend of mine did a home using this system in Rio de Janeiro where you easily get over 42C (107 F) outside in the summer. It works fantastically.
Energy in Brasil used to be way less expensive, and traditional masonry and concrete construction is not very friendly to insulation unless you do like the germans that have double walls with the insulation in the middle. So, culturally, insulation is kind of an alien concept for a lot of people and even engineers.
https://en.wikipedia.org/wiki/Net_metering
That's kinda fucked up. But well, for my friend in the South, where winters are miserably cold and houses have no heating infrastructure, using the accumulated energy credits during the winter is easy. Heck, there are even crypto-mining heaters available these days, so it kinda works best for him I guess?
Yeah. My air conditioners are running pretty much 24/7.
> You don't even need to wait for winter to use those credits.
Depends on how much energy you generate. Solar power can easily generate the amount of energy consumed by air conditioning. Just gotta make sure peak summer output generates enough surplus to cover the needs of the other seasons. My solar system generates between 400-1100 kWh/month. It's always been enough and if my needs change I can always expand capacity.
> And if you have money to do so, buying an electric car can be also a good usage of those credits.
Absolutely. That's my next goal. I don't want to pay for gasoline anymore. I think it's still a bit too early for that, electric cars need to get cheaper for it to be truly worth it.
Didn't know about this! Added to the wishlist.
I completely covered my home's front rooftop with solar panels and they paid for themselves in about three years time. They're so effective that we have politicians campaigning against government incentives for renewable energy. Too many rich people and corporations are benefiting it seems, can't have that.
This is despite the fact that they don't actually pay us for the energy we generate. They give us "kWh credits" which expire if unused after one year. Were it not for that, I'd have even more solar panels in service.
Even if they were transferable, I'd probaby get cents on the dollar for them. They expire so they must be worth less than a real kWh. Why would anyone buy these things otherwise? If they were worth the same, people would simply pay their energy bills instead of buying credits from me.
Unfortunately I can’t diy myself with connecting to network (unless I get massive battery which pushes payback to same 10yrs or so).
DIY simply not feasible for many people, esp in places with stringent laws or where houses changes hands frequently.
https://news.ycombinator.com/item?id=39339129
How much would it cost to build a system like mine in NZ? In other countries?
but not oil, russian oil "Brazil’s imports of Russian oil products soar" https://www.ft.com/content/7ebb679e-099e-49ac-a750-73ca46538...
"Brazilian imports of diesel from Russia last year soared 4,600 per cent while purchases of fuel oil rose by almost 400 per cent, in a $8.6bn boost to the Russian economy as the war in Ukraine enters its third year.
Brasília imported 6.1mn tonnes of diesel from Russia in 2023, a 6,000 per cent increase from the 101,000 tonnes the previous year. The value in dollar terms increased 4,600 per cent from $95mn to $4.5bn"