-
@Snowy said in Solar Power and Storage - a nerd's view:
Who else is doing batteries?
So in this part of the world for lithium you have known brands like Tesla, LGChem, sonnenBatterie, Enphase, and I think Fronius do a hybrid unit. After that there is a whole heap of Chinese manufacturers entering the market.
Lead acid is always there, but the fact it is a well-known technology doesn't mean it is bulletproof. Control systems are the problem and it isn't actually a very common technology compared to Lithium, which is becoming plug n play at a rapid rate of knots.
e.g. My PW1 took the techie a few hours to wire in correctly, because the inverter hooked up to a Battery Management System which hooked up to the PW1 itself. Now they're coming as all-in-ones with an inbuilt inverter (Tesla PW2) or compatible plug tech for a wider range of inverters. Less piss-farting around.
There are also a couple of quirky options like Redflow (poorly named IMHO) ZCell - using a Zinc-Bromine (ZnBr) fluid solution for very stable operation. The issues are:
- 80% round trip efficiency (put in 10kWh, get 8kWh out) compared to lithium which is 90-94% depending on manufacturer.
- Cost per kWh - not much volume in the market keeps prices relatively high
https://redflow.com/products/redflow-zcell/
However I know that these ZnBr units are being used by telcos in NZ as part of the power setup for things like 4G towers - even in the Alps! Some of the mobile phone infrastructure has solar as the primary source with one of these ZCells in a shed next to it (they also have a diesel gen in there but usage is < 2% of the time I think).
I have considered off grid, but I think we would still need to go lead acid if we did that and then I would need a generator, so went off the idea.
The issue with off-grid is the entry cost - you need to account for about 4 days without sun, and not your most frugal estimate either; average usage + 50% for emergencies IMHO. Probably starting at NZD$50K ish.
If you had a "lifestyle block" and needed to pay the power company $150K to string in some power, it becomes well worth it.
-
@NTA said in Solar Power and Storage - a nerd's view:
The issue with off-grid is the entry cost - you need to account for about 4 days without sun, and not your most frugal estimate either; average usage + 50% for emergencies IMHO. Probably starting at NZD$50K ish.
That's why I went of the idea - not the cost - the days without sun. If we get a Nor easter we can end up in cloud. Elevated section that looks out sea so it can blow straight into our place and not having grid backup could be a problem (hence the generator comment).
Thanks for the info on batteries will look into those.
We do have a "life sentence" block but I have grid power. Three phase to my new barn which is about 300 hundred meters from the house site. I did meet some people the other day who are off grid and you have exactly described their situation, 150k to get the power in, or 50k for off grid batteries, generator, etc. They actually really like it though.
-
O.K. so I have more info. I only have one section of roof that is north facing and 12 to 15 deg pitch, so can put some panels on there with appropriate fittings for angle. My architect / structural engineer (very useful dual skills in one guy) has a good solution to get some more on the house. They can be mounted off the poles that are holding up a huge north facing deck and we can get our 36 deg on those as well. Below eye line out of sight and IIRC they are usually about a mtr wide so I can get 25 panels going easily.
I think I'm going to go with about 10kw. We will end up with two electric cars so going to need it.
Next questions, recommendations on panels? It's been a while since I did much research on this. My last ones were LG, good quality but was before micro inverters were around (just). If I understand it correctly microinverters mean that you still get power from the full array even if one panel is shaded?
So microinverters?
Brand of panels?
Size of panels? I assume just go high 400+, so that I don't need so many? How many panels have you got for 6.5kw @nta ? I'm thinking 25 for us to get my 10kw.
Assume monocrystalline is best?Any ideas / tips welcome.
-
@Snowy you can either go the full microinverter route, or the halfway point which is power optimisers. Depends on the brand of panel and/or inverter you get.
You're right in that microinverter/power optimisers mean that each panel's voltage is independently tuned regardless of partial shading etc. You effectively have one "string" per panel balancing voltage and therefore output.
If you have everything facing the same direction with no likely partial shade situations, you may not even need them.
Besides that, for your situation, given cash is no object, a Tier 1 panel like LG would be good, and something in the 350kW+ range. Most installers will have packages in sizes 4-10kW they can give you, and best to ask for a couple of quotes with a couple of installers IMHO.
-
@Tim massive, massive infrastructure build. Only China could do this. USA maybe if they pulled finger.
This sort of tech could assist Australia get where it needs to be with renewables across state lines, but the cost is prohibitive.
Better to go "standard" HVDC to get the wind and solar farms connected.
-
Yeah, surely local micro generation is a better solution. There may be some population "control" issues in China as well.
These look good:
*"The International Energy Agency says solar electricity is now being made more cheaply than any other method of production. But solar panels currently only convert around a fifth of the sun's energy that falls on them into electricity.
Sunlight is made up of the spectrum you see in a rainbow and silicon, found in nearly all solar panels, is best at converting the red part into electricity.
But UK-based company Oxford PV is combining silicon with a material called perovskite - a semi conductor mineral with a crystal structure of titanium calcium oxide - which turns the blue wavelengths into electrical energy. This chemical sandwich can increase the panels efficiency to 30-40%.
They are going into production this year and expect early applications to be on rooftops where customers want to maximise the wattage from a confined area."*
-
@Snowy all comes down to cost - solar panels that were 11% efficient were the norm for domestic applications ten years ago.
Mine are 5 years old and were about 18% efficient at install (they degrade about 1% of existing yield per annum so would now be getting down to 17%)
Most of the Tier 1 panels were 20-22% at the time, and always getting better. That's why the wattage increases without panel size increasing - efficiency.
Mine are 250W but 350W+ is fairly normal now.
-
@NTA Mine were 250w as well. From memory they had a 20 year warranty to operate at 80% plus (of original output) which actually sounds a bit low. Pretty hard to measure that in a home system though on any given day with the sunlight variable.
No idea what the Oxford ones will cost but if you are reducing the number of panels by that much could be economic. Say a third more efficiency on top.
These look interesting too:
https://www.sciencedirect.com/science/article/pii/S2090447913000403
The tech keeps changing so you have to take the plunge at some point I guess.
The other issue is supply with Covid and ships not being unloaded in NZ. Hopefully that will be fixed before I want them and isn't a problem as yet. -
I decided to reply here as it seemed like a better place for it. Also: the Powerwall is celebrating its 5th birthday today, so yay me.
@pakman said in Electric Vehicles:
Interesting language. A lot of angry comments under that article as well
Beyond the fact that WUWT is a known climate science denial/doomscare blog, and Eschenbach is not considered scientifically literate by any reasonable measure, I want to hone in on a couple of points he uses:
The NREL document he's quoting for solar at "8.3 watts per square metre" is from 2013
Significant improvements have been made since then , with cell efficiency doubling, so maybe quote that figure above 17 watts/sqm or more - due to better inverter tech. Ignoring deployments that use tracking tech to extract even more than the stated efficiency.Wind turbines quoted at 2MW is on the small side. Land-based turbines are typically 3MW or above for grid scale installations. Twice that or more for offshore turbines - average turbine size in Europe installed in 2019 was 7.8MW. I'd be happy to say that average installed wind turbine capacity for 2021 onward is 4MW and leave it at that.
(Unfortunately both of these are examples of the denier scepticism: use old or current figures like they're never going to get better).
We've just improved both technologies by 100%, and therefore halved any figures used in the article for time, land use, or labour. Nice. That's without even adding any firming storage or pumped hydro to support the capacity factor of wind/solar.
Nuclear is not financially viable in any of these scenarios, however I think there will continue to be development here to help with the last 25% of need on the grid. Governments will probably end up carrying the can for that.
I'm in no way belittling the challenge. Net zero is a freaking huge effort and the inaction to date hasn't helped kick it along except in certain cases e.g. R&D under certain schemes. We'll basically have to pivot all mining of fossil fuels into mining of other things to keep the movement going, as one example, and electrifying heavy industry will be tough.
On the plus side for the article: looking at the problem in terms of all FF burned is really key. A lot of studies just concentrate on the electricity grids and manufacturing, and forget the billions of cars running around - particularly here in Oz where we have no emissions standards.
At the same time, we need to consider the transformative nature of something like an EV: A petrol engine might convert about 20% of the power in liquid fuels to energy at the road (losing a lot to heat), while electric cars are close to 80% on the same measure. Already you're achieving a massive difference with each FF car taken off the road, even considering the manufacturing differences for the battery - which again will get more efficient over time.
An overarching point is the efficiencies in supply chain: if your car runs on wind/solar, you're not shipping or refining petrol, and so you're not burning crude to ship petrol. It is a force multiplier effect. Then you have the downside of replacing solar/wind every 20-30 years, which produces the upside of getting more efficient tech replacing old tech more rapidly than a 50-year coal or nuclear plant, but what about the waste? We'll make new recycling industries to ensure we keep a closed loop on things? Who is paying for that?
Here come the Unintended Consequences
-
@NTA said in Solar Power and Storage - a nerd's view:
Here come the Unintended Consequences
The consequences are obvious - we're going to pay more for electricity. And the more we pay for wind and solar the less we're going to decarbonise our grid per dollar spent compared to alternatives.
-
@antipodean said in Solar Power and Storage - a nerd's view:
@NTA said in Solar Power and Storage - a nerd's view:
Here come the Unintended Consequences
The consequences are obvious - we're going to pay more for electricity. And the more we pay for wind and solar the less we're going to decarbonise our grid per dollar spent compared to alternatives.
You're funny.
-
@NTA said in Solar Power and Storage - a nerd's view:
@antipodean said in Solar Power and Storage - a nerd's view:
@NTA said in Solar Power and Storage - a nerd's view:
Here come the Unintended Consequences
The consequences are obvious - we're going to pay more for electricity. And the more we pay for wind and solar the less we're going to decarbonise our grid per dollar spent compared to alternatives.
You're funny.
I almost bit
-
@NTA said in Solar Power and Storage - a nerd's view:
@antipodean said in Solar Power and Storage - a nerd's view:
@NTA said in Solar Power and Storage - a nerd's view:
Here come the Unintended Consequences
The consequences are obvious - we're going to pay more for electricity. And the more we pay for wind and solar the less we're going to decarbonise our grid per dollar spent compared to alternatives.
You're funny.
Evidence. South Australia, California and Germany. Right now South Australia has the most expensive electricity in Australia:
What a coincidence.
Then we look at Norway, Sweden, France compared to Germany:
Strange how spending hundreds of billions of euros on wind and solar still hasn't decarbonised Germany's grid as well as France's.
Data's funny that way.
-
@antipodean said in Solar Power and Storage - a nerd's view:
Strange how spending hundreds of billions of euros on wind and solar still hasn't decarbonised Germany's grid as well as France's.
You're a fan of government expenditure on nuclear?
That's weird, given your pissing and moaning about the cost to future generations over COVID
-
@NTA said in Solar Power and Storage - a nerd's view:
@antipodean said in Solar Power and Storage - a nerd's view:
Strange how spending hundreds of billions of euros on wind and solar still hasn't decarbonised Germany's grid as well as France's.
You're a fan of government expenditure on nuclear?
More than subsidising rent seeking solar farms.
That's weird, given your pissing and moaning about the cost to future generations over COVID
Not weird at all. One has clear measurable benefits. Why are you conflating the two?
-
@antipodean said in Solar Power and Storage - a nerd's view:
@NTA said in Solar Power and Storage - a nerd's view:
@antipodean said in Solar Power and Storage - a nerd's view:
Strange how spending hundreds of billions of euros on wind and solar still hasn't decarbonised Germany's grid as well as France's.
You're a fan of government expenditure on nuclear?
More than subsidising rent seeking solar farms.
Rent seeking? So you're a big supporter of fossil fuels then?
-
@NTA said in Solar Power and Storage - a nerd's view:
@antipodean said in Solar Power and Storage - a nerd's view:
@NTA said in Solar Power and Storage - a nerd's view:
@antipodean said in Solar Power and Storage - a nerd's view:
Strange how spending hundreds of billions of euros on wind and solar still hasn't decarbonised Germany's grid as well as France's.
You're a fan of government expenditure on nuclear?
More than subsidising rent seeking solar farms.
Rent seeking? So you're a big supporter of fossil fuels then?
Are you capable of discussing something without inventing arguments for others? I'd consider $50+ billion in exports as slightly better than rent seeking.
-
There appears to be no allowance for micro generation, so grid becomes irrelevant. I will be grid connected but more likely to supply than draw. Macro generation and distribution should be confined to the past.
Subsidies for micro would be a more efficient way to achieve the goal by 2050 than investing in large scale sources.
Solar Power and Storage - a nerd's view