Viewing a single comment thread. View all comments

smsutton t1_ja1dezj wrote

Don’t really need the land. You need to network all the rooftops.

87

landodk t1_ja1oai2 wrote

Probably not even all rooftops. Just focusing on the large flat commercial rooftops would be huge, and lower installation/maintenance costs

38

littleday t1_ja1yiyd wrote

You’d need more than that, Western Australia 45% of all domestic rooftops have solar, we cover most of Our needs from solar, but it’s the storage that’s the issue for night time. It can be done, but battery tech needs to get cheaper and it is. In Australia you can buy a 6.6kW system with a battery for 12k USD and it would cover most house holds needs.

22

aquarain t1_ja39ono wrote

The iron flow batteries are on the way. Much longer duration, higher cycles and way lower cost. Consumes some of the energy though.

3

mikasjoman t1_ja3qn8s wrote

I'll trust it when I see it at the store. So much tech has been on its way for a decade, "just around the corner" it's ridiculous to even mention them by now.

10

bejamamo t1_ja59n8e wrote

But solid state battery are going to REVOLUTIONIZE the way we think about battery storage /s

1

pinkfootthegoose t1_ja3v5bq wrote

iron flow are only good for utility scale storage. moving parts and all that need maintenance.

1

sunshine-thewerewolf t1_ja25h3x wrote

I have 2 rooftops that would be prime for solar. Most my neighbors also have prime spots. Could easily be feeding the grid and have our own backups. Seems like an easy win

2

typing t1_ja1ofoe wrote

This is much better than a centralized solution. From a defensive point of view, if you keep all your energy infrastructure in one place it makes the whole country vulnerable to an attack. However if you used this roof top idea it would be fully decentralized making each unit area independent of others, isolating attacks

15

arfbrookwood t1_ja1qu0y wrote

Yeah like why is a carrier even a thing. Just use 2000 rowboats.

−11

OcculusSniffed t1_ja204mc wrote

I am fascinated that you think those are an even comparison.

4

Hei2 t1_ja4ab4j wrote

Don't you know? Solar farms are staging points for attacks.

2

arfbrookwood t1_ja3akw1 wrote

I don’t. Just as i don’t think that thousands of decentralized systems of solar paneling are equal to a central power plant well built, planned, funded, and staffed.

−2

Amazingawesomator t1_ja1fui9 wrote

I always find those estimates of things like "just fill south dakota with panels" as a bit rediculous, heh. Plenty of rooftops on my neighborhood dont have solar; i dont know of any businesses in my area that have solar.

I generate more than i use, and only ~1/2 my roof is panels (i didnt want them to be garish, so they are on the back of the house).

I doubt much extra land is needed

12

peter-doubt t1_ja1ku9n wrote

Plenty of storage sheds... With simple roofs and no major obstructions... But they're largely unused, too.

3

Dirty_South_Cracka t1_ja1fiy8 wrote

This is what few people realize... its not the local generation that's a big deal. Any moron who can turn an electric drill can setup a solar array. It's the infrastructure needed to deliver that power reliably on a distributed grid that is difficult and expensive. I'm not even sure if current copper production/availability would survive trying to accomplish such a feat. Much less the amount of lithium needed to make batteries. We're simply trading one eventuality for another.

Solar is doomed as a full replacement for carbon until a cheap battery (sodium maybe) that can be recharged 1000's of times and recycled can be developed.

We don't need more solar technology, we need a better battery chemistry... and we need it quick.

4

pinkfootthegoose t1_ja1k6g8 wrote

you don't need lithium batteries for batteries that stay in place since their weight would be irrelevant. You can use materials more conducive for the application either commercial or home use.

Also we already have a distributed grid... our current (pun) one.

Also there is already regulation in place for power cut offs for power generation feed back and is not that expensive.

Industry is very aware of the need to move away from lithium ion for in place electricity storage and is spending billions on research with some alternatives already being built.

15

Dirty_South_Cracka t1_ja1kwf9 wrote

I would love to see more info on how that works. Are they converting DC back to AC for distribution on our current grid? Can our current grid handle DC transmission without significant loss cheaply? I'm not trying to be difficult, I'm geniunely curious.

1

pinkfootthegoose t1_ja1olke wrote

of course it's converted to AC.. you need to do that to use it in your house anyway.

Well DC is only used for HVDC lines as far as I know, at least day to day for most people.

people without batteries rely on net metering. They use to solar panels during the day to either reduce the amount of power they get from the power company or they even produce a surplus during the day and send some back up the line for local distribution. This reduces their power bill but they still rely power company for power since for safety reason they have the aforementioned power cut off so line workers aren't zapped. So no you generally can't use your panels if you are grid connected with no batteries though in theory you would just manually disconnect from the grid and power the house during the day depending on how much you generate and how much you need.

For those with a battery but are connected to the grid it's a bit different. They of course use the panels to power their house but also charge up batteries for later use and once the batteries are full send power back to the grid. They of course use the batteries at night or during inclement weathers when there isn't much sun. If the power from the grid goes out they can instantly switch to solar, battery or a combinations of the two depending on the circumstances.

5

djkuhl t1_ja1xzn2 wrote

> Solar is doomed as a full replacement for carbon until a cheap battery (sodium maybe) that can be recharged 1000's of times and recycled can be developed.

Iron Redox Flow Batteries are being deployed at grid scale (only two 75kwh batteries to start) for the first time this year. Super cheap, recyclable, and can last 50-100 years. Now we just have to worry about running out of iron, salt, and water.

6

TheNatureBoy t1_ja1j5m9 wrote

What if during the day time the grid powers pumps to fill damns?

2

Cerran424 t1_ja4jbb2 wrote

As an engineer who has worked on several pumped storage projects the big challenge there is location. If you are going to pump water uphill you have to get it from somewhere. In drought stricken areas like CA that’s not super realistic. It’s also limited by geography and the capex costs are very high.

I’m currently working on a pumped storage system but it’s in rural Montana where water is plentiful and building restrictions aren’t as challenging and they still have issues with power wheeling agreements. Simply put pumped storage is far more complicated than most people realize.

2

TheNatureBoy t1_ja4pbpv wrote

What do you feel about the current project at the Hoover Dam?

1

Cerran424 t1_ja4r5hm wrote

It has a lot of technical hurdles to solve before it’s a viable project especially with the current drought situation at Lake Mead.

1

TheNatureBoy t1_ja4s63q wrote

Sorry to bother you again. How does the water level effect the process? Do the pumps just pump to a fixed height? (I understand fluids up to the Navier-Stokes equation)

1

Cerran424 t1_ja4srkv wrote

The water level question is more how much water can be recycled given the discharge requirements and flow downstream.

You would likely have to design the pumps to lift water to the maximum height of Lake Mead.

2

TheNatureBoy t1_ja4v5yl wrote

Damn, that sounds like a tremendous energy loss with a low lake.

Thanks for the response.

1

Cerran424 t1_ja4svx9 wrote

I’m mainly making an educated guess based on requirements of past projects.

1

pinkfootthegoose t1_ja3vf60 wrote

during the day the dam can just stop letting water flow, they fill themselves.

1

Cerran424 t1_ja4jhmh wrote

Can’t just stop letting it flow in most cases because of downstream consequences like irrigation and navigation.

2

peter-doubt t1_ja1kof8 wrote

You're storage will likely be 60% efficient... a start, but too inefficient to be a reliable backup. Why not use wind to do this when demand isn't near full production?

−6

peter-doubt t1_ja1keuz wrote

There's other storage methods, but they don't contradict your point.. they're all too expensive to make solar the go-to at short distances.

1

billdietrich1 t1_ja2mg9o wrote

> we need a better battery chemistry... and we need it quick.

Multiple are being developed, some have been deployed (e.g. https://cleantechnica.com/2019/02/03/sodium-sulfur-battery-in-abu-dhabi-is-worlds-largest-storage-device/). But we don't need them "quick"; we have plenty of room for more renewables in existing grids before we absolutely must have storage.

1

Dirty_South_Cracka t1_ja306ir wrote

I've been hearing that same bullshit for the last 20 years. We've been perpetually almost there sine the early 2000's. Molen salt was supposed to be the wonder battery then.

0

billdietrich1 t1_ja34qk7 wrote

Batteries have greatly improved in performance and cost, and we're deploying them at utility-scale. And chemical battery is far from the only form of storage.

2

Agillian_01 t1_ja39mrz wrote

I read a news article a couple days ago about a group of researchers in one of our universities creating a new sodium addative of sorts to use in Lithium-ion batteries. It seems to increase the lifespan of these batteries by about ten-fold. I believebit had to do with li-ion batteries using up sodium in the batteries to self-repair damage caused by charging and discharging the batteries. By changing the types of sodium in the battery, the amount of sodium used in each cycly was greatly reduced. I am by no means an expert on the matter, so I hope this made sense. I believe the article was released in one of the major physics magazines.

1

aquarain t1_ja39vyd wrote

Distributed virtual power plants are a thing now, and will only grow. As with anything else, as the units go up the price per comes down.

1

jeffyoulose t1_ja1p2h8 wrote

What about using photosynthesis to create a ton of biomass stored energy in the form of plants that can be used as kindling to warm up the house at night?

0

DiablolicalScientist t1_ja1wi6k wrote

Right... And aren't these panels needing replacement every 7 years or something?

0

Dirty_South_Cracka t1_ja1wz8b wrote

Most modern residential panels are rated for 80%+ output for 25 years. I think that's actually pretty impressive.

6

Talamakara t1_ja259j8 wrote

No solar panel on the planet exceeds 33.6% efficiency, it's called the Shockley Quizer Effect.

1

Dirty_South_Cracka t1_ja2yab5 wrote

Efficiency and output are two completely different metrics. That being said, 33.6% efficient is pretty damn good considering there are no moving parts. The most efficient steam turbines are only about 45% efficient and that is modern technology. The ones in use today are right around 35%.

5

pinkfootthegoose t1_ja3vptu wrote

they come with 25 year warranties to produce something like 80 or 85% of their original power for 25 years.. though they are expected to actually last something like 30+ years. least the new ones.

1

billdietrich1 t1_ja2m9w2 wrote

Better to put solar PV on light frameworks above parking lots, roads, road medians, etc. Easier to install and maintain, and we have plenty of space there.

1

-The_Blazer- t1_ja51712 wrote

Utility solar is the cheapest form of solar though. There are very real benefits to industrialized mass-scale infrastructure.

1

Neo1331 t1_ja5e2x1 wrote

This is why I like the California requirement to put solar panels on new residential building. The power generation is crazy.

1

tickleMyBigPoop t1_ja3q3za wrote

Lol I’m not networking the solar panels i bought for general use unless someone pays me.

Right now it goes straight into my battery system.

0