Solar Just Hit a Record Low Price in the U.S • Hacker News Board

Re: Solar Just Hit a Record Low Price in the U.S

#341

Post by mrb » Thu, Jul 12, 2018, 7:10 PM UTC

opo wrote: post #319

mrb wrote: post #294

Earlier quoted context omitted.

Your chart is even less granular than mine (hourly vs half-hourly), and it has a timezone conversion error. The source they use (ISO New England - https://www.iso-ne.com/isoexpress/ ) shows the peak of a typical October month to be between 3pm-4pm and not 6pm-7pm: https://i.imgur.com/5rWlnVO.png (the 3 hours difference is the timezone offset between east coast and west coast.) My chart, if you look closely, has a gra…

>Your chart is even less granular than mine (hourly vs half-hourly), I think you might have posted the wrong image to imgur. You linked to: https://imgur.com/wTIt5tg I am not sure how you are getting half hour indications on that weekly chart. >...ISO New England data more clearly shows the peak to be between 2pm-3pm for a typical summer month: Yes, that was why wikipedia says: >...It depends on the demography, the e…

«I am not sure how you are getting half hour indications on that weekly chart.»

See https://i.myimg.io/wi9J.png

«The EIA web site was talking about October»

This is why I also showed an October chart, with a peak at 3-4pm.

But, yes, peak can vary with weather, time of year, etc. All I'm saying is that in general—not always—peak PV generation coincide reasonably with peak electricity demand.

Re: Solar Just Hit a Record Low Price in the U.S

#342

Post by stale2002 » Thu, Jul 12, 2018, 7:11 PM UTC

hueving wrote: post #303

stale2002 wrote: post #298

Earlier quoted context omitted.

Highly polluting energy sources are not paying to clean up the environmental costs that they produce. Maybe THEY are the free riders.

From some externality to society perspective, sure. But that's definitely not true of a grid operation cost perspective. A coal power plant does not get paid retail rates for the power it generates. The utility company charges more precisely to pay for transmission and the people to maintain it.

Ok, so what?

Let's punish the free riders and reward the people who are reducing the total societial cost of energy.

The fact that solar owners get access to the energy grid for free seems like a clever way to punish the free riders by increasing their costs in a roundabout way.

Don't want to pay the higher costs for your power grid? Then upgrade to cleaner energy! Sounds great.

Re: Solar Just Hit a Record Low Price in the U.S

#343

Post by agumonkey » Thu, Jul 12, 2018, 9:57 PM UTC

epistasis wrote: post #331

agumonkey wrote: post #210

Earlier quoted context omitted.

any curated list of place to follow to stay up to date ?

No curated places for the Bay efforts from each tech that I know of. However there are a few news outlets that are pretty solid: https://www.greentechmedia.com/ https://www.utilitydive.com

appreciated

Re: Solar Just Hit a Record Low Price in the U.S

#344

Post by Kliment » Thu, Jul 12, 2018, 10:04 PM UTC

sokoloff wrote: post #326

Kliment wrote: post #316

Earlier quoted context omitted.

Data has plenty of value, and is often copied without authorization, but putting that aside, nobody would be stealing anyone's power. It gets produced in one region, used locally, and excess sold to the next region, where the same thing repeats. You already paid for the power entering your region so you can't steal it and you'll sell it on if it makes sense to do so. This is already how gas pipelines work for example…

> Either way the metering happens at regional boundaries so there's no stealing involved - both sides of the meter need to be in agreement before any power flows. Play that out a bit. Suppose you have a 500MW or 1000MW transmission line. It normally has a 1% loss. Today, you notice that it has 1.25% loss. Maybe someone's stealing power. What do you do? Shut off the transmission line entirely?

At the demarcation points is where power is measured. If you have losses you can tell which side they are on, and then that side can decide whether they are worth investigating or not.

Re: Solar Just Hit a Record Low Price in the U.S

#345

Post by cgdcraig » Fri, Jul 13, 2018, 4:57 AM UTC

dragontamer wrote: post #334

cgdcraig wrote: post #314

Earlier quoted context omitted.

Cold energy storage has always had the problem of utilization and capital cost. You need to buy the storage system and then that storage system may only be useful for 3-6 months of the year during 6 hours of the day. From a thermal efficiency perspective they're great but in general they get offed by the economics. For the price you'd end up gettinf better value off a battery storage system to do load shifting.

Ice storage seems uneconomical. But chilled water (40F / 5C) is reasonable. If you see it from a total-cost-of-ownership, the chilled-water + air conditioning unit is overall cheaper than you'd expect. The air conditioner doesn't need to be rated for the peak-loads anymore, but can run more continuously at lower temperatures (ie: at night to store chilled energy into the water). So you downsize your air conditioner,…

Dealing with cold energy(coolth) storage whether it's in ice or chilled water is tricky mostly because of the capital cost involved with adding a storage system that can only do one thing, namely store cold. They're great for specific regions where you'll be using them on a daily basis. Chilling water outside of the peak times for use during peak cooling has been studied a lot in litterature there's a recent article here about storing excess solar energy in cooling energy:https://www.sciencedirect.com/science/article/pii/S221067071... , the main problem with the system is one of practicality. In order to effectively use the cold storage you need to use liquid cooling like the ones used in commercial buildings, that or switch to a water source chiller with a cooling tower. You can build it, but whether the total cost of that system is less than buying a bigger AC unit and paying more for power depends entirely on local conditions(seasonality,diurnal temperature changes, whether you pay for demand as well as power and whether you're on time of day metering).

------------ Using it for winter and summer does increase the utilization and would be best practice but places with winter/summer seasonality have a golden zone where you don't need active heating or cooling. If you're below 24c and above 18c you don't need much energy to maintain thermal comfort, provided you're not in a high humidity environment. During the winter it's better to use solar collectors with a thermal syphon for heat collection instead of stocking up heat since peak thermal demand occurs at night.

------------ They're known as earthpipes or earth hear exchangers and they come with their own problems, namely proximity to surface and thermal load imbalance over seasons. The earth is a really shitty thermal reservoir because it bleeds heat out the side and the top, the really big thing that it has going for it is that it's free. When you use the system in an environment thats either mostly hot or mostly cold you change the ground temperature in the long run, either increasing it or decreasing it over time. This in turn affects the ability of the system to condition air, there's also the problem that it can only bring the air temperature up to that of the ground during winter so you still need a heating system to supplement it; works great for cooling though. Basically the system gives you thermal energy at no operational cost(other than the fan) but you have to either accept whatever temperature it gives you or have a way to further condition it. Earthships generally use the sun in the winter to bring the temperature up during the day and have a thermal mass inside the house that maintains the temperature at night.

Re: Solar Just Hit a Record Low Price in the U.S

#346

Post by opo » Fri, Jul 13, 2018, 5:23 AM UTC

mrb wrote: post #341

opo wrote: post #319

Earlier quoted context omitted.

>Your chart is even less granular than mine (hourly vs half-hourly), I think you might have posted the wrong image to imgur. You linked to: https://imgur.com/wTIt5tg I am not sure how you are getting half hour indications on that weekly chart. >...ISO New England data more clearly shows the peak to be between 2pm-3pm for a typical summer month: Yes, that was why wikipedia says: >...It depends on the demography, the e…

« I am not sure how you are getting half hour indications on that weekly chart. » See https://i.myimg.io/wi9J.png « The EIA web site was talking about October » This is why I also showed an October chart, with a peak at 3-4pm. But, yes, peak can vary with weather, time of year, etc. All I'm saying is that in general —not always—peak PV generation coincide reasonably with peak electricity demand.

>...See https://i.myimg.io/wi9J.png

OK, for many reasons we are just going to have to agree to disagree on that chart. (I just measured https://imgur.com/wTIt5tg and on my machine it definitely is more than 41 pixels between each day but that doesn't mean each pixel is representing exactly x minutes of time, there is no indication on the chart each pixel actually represents 35 minutes or if it is interpolated data, etc. To me it gives a rough showing of energy demand over a week.)

>...This is why I also showed an October chart, with a peak at 3-4pm.

It isn't clear to me why there would be peak demand at 3-4 in the afternoon in an October day. As the EIA site says:

>...During this period, usually in the early evening, operators need more generating capacity–including more costly "peaking" units. Both day-ahead and long-term forecasts account for these peaks to ensure the assignment of adequate capacity.

>...But, yes, peak can vary with weather, time of year, etc. All I'm saying is that in general—not always—peak PV generation coincide reasonably with peak electricity demand.

I think we basically agree on that. Peak PV generation is probably closer to noon, but in general more energy is needed during daylight hours than at night. (And obviously a hot sunny day will spike energy usage for cooling and solar PV is a perfect fit at that time.) The problem to me is when people over simplify this issue. The amount of demand will vary in different areas at different times of the year and even when it is raining, there will still be demand. I've always been a supporter of solar power but there is a lot of handwaving going on when people say we can get 100% of our power from solar and wind without there being some huge advances in energy storage.

Re: Solar Just Hit a Record Low Price in the U.S

#347

Post by ksec » Fri, Jul 13, 2018, 10:49 AM UTC

philipkglass wrote: post #338

ksec wrote: post #323

Correct me if any of the maths below are wrong. Eagle Solar Mountain Solar Farm ( 300 MW ) will have an annual production capacity of over 900 million kilowatt hours (kWh) once completed. The Moapa Band of Paiutes has become a national clean energy leader and will host in excess of 600 MW of solar on the 72,000-acre reservation. [1] For example, the Topaz Solar Farm [3] has an annual production capacity of 1200 milli…

The $2 billion in the article you linked seems to refer to NV Energy's "latest tranche of renewable projects totaling over 1 gigawatt." The cost of the Eagle Solar Mountain Solar Farm does not appear to be broken out specifically in that article. The Moapa Band of Paiutes is presumably not dedicating most of their reservation's land to solar generation. Most of the Topaz Solar Farm's land is dedicated to solar genera…

I see. Sorry I don't follow much US politics.

I know Nevada are basically a desert, which is perfect for Solar Panel and electricity, does the Federation nature, forbid a super scale Solar Farm in Nevada to power the rest of US? And who owns the grid in US? Government?

Re: Solar Just Hit a Record Low Price in the U.S

#348

Post by Jedd » Fri, Jul 13, 2018, 12:49 PM UTC

thinkcontext wrote: post #247

Jedd wrote: post #226

Earlier quoted context omitted.

> You don't need 1:1 storage for solar production... You seem to be referring exclusively to solar photovoltaic. Solar thermal generation has quite a different, evening-friendly, distribution curve.

True, though the article was talking about PV. I haven't followed closely recently but my impression was solar thermal has not delivered as promised. Things like Ivanpah was relying on natural gas more than expected. Is this an accurate impression?

> True, though the article was talking about PV.

Perhaps, but we're better than conflating solar pvc with solar thermal - especially when we talk about large scale deployments, and even more especially when we talk about systems that incorporate Big Storage (batteries or otherwise).

Parent (to your comment) wasn't specifically PVC, parent (to them) wasn't either (more about true cost), and parent to them was bemoaning the common misunderstanding around how pricing works, rather than ethics / feasibility / ambiguity around underlying technology.

> I haven't followed closely recently but my impression was solar thermal has not delivered as promised. Things like Ivanpah was relying on natural gas more than expected. Is this an accurate impression?

My impression is that solar thermal is going to provide a much more scalable solution, especially in terms of avoiding the duck curve (or at least mitigating the impact of same). I see PVC + batteries being one of those tech combinations that works reasonably well in front of, as well as behind, the meter ... but solar thermal's definitely grid-level.

Re: Solar Just Hit a Record Low Price in the U.S

#349

Post by philipkglass » Fri, Jul 13, 2018, 4:46 PM UTC

ksec wrote: post #347

philipkglass wrote: post #338

Earlier quoted context omitted.

The $2 billion in the article you linked seems to refer to NV Energy's "latest tranche of renewable projects totaling over 1 gigawatt." The cost of the Eagle Solar Mountain Solar Farm does not appear to be broken out specifically in that article. The Moapa Band of Paiutes is presumably not dedicating most of their reservation's land to solar generation. Most of the Topaz Solar Farm's land is dedicated to solar genera…

I see. Sorry I don't follow much US politics. I know Nevada are basically a desert, which is perfect for Solar Panel and electricity, does the Federation nature, forbid a super scale Solar Farm in Nevada to power the rest of US? And who owns the grid in US? Government?

The United States has multiple regional grids, operated by organizations called RTOs or ISOs (Regional Transmission Operators, Independent System Operators). Components of the grid, including transmission lines, may be owned by government agencies or by private companies, though private companies are more common.

As I mentioned in another comment, the hardest part of building big interstate transmission projects in the US is getting approval from every state and land owner between two distant points. 4 out of 5 involved states can approve a plan quickly but then the plan can languish for years trying to get approval from the 5th state involved.

Long distance transmission projects do get built, but they generally take a long and uncertain time to reach approval. That's one of the factors that prevents sunny states from just exporting solar power to less sunny, more densely populated states. The other big factor is that these big infrastructure projects are also expensive to construct, but in my opinion it's the delays and uncertainties that are the bigger obstacle.

Re: Solar Just Hit a Record Low Price in the U.S

#350

Post by honestoHeminway » Sat, Jul 14, 2018, 7:52 AM UTC

inputcoffee wrote: post #153

jartelt wrote: post #140

Earlier quoted context omitted.

This comment gets made in every single solar article put on HN. The true price of solar is what the market is willing to pay for it. If the solar was ruining the grid or was way more expensive than what it seems, we would not keep seeing solar installed at this pace and at these costs. We need to get out of the mindset that all power generators need to produce a steady amount of power 24/7. A flexible grid made of ma…

You misunderstand the sense of "true" here. The point is not that the "true" price in the sense of what it ought to be. It is the "true" price in the sense of what the market is actually paying for the service. When people put out the number $23, they compare it with the cost of power and wonder why, if it is so much lower, it doesn't already swamp the current solution. So the purpose of the comment is to explain tha…

We dont pay the true price of coal, coal is a overdrawn credit-card on future generations where you cant bail by death.