How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream • Hacker News Board

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#211

Post by lostmsu » Mon, Apr 23, 2018, 7:01 PM UTC

Retric wrote: post #207

hadlock wrote: post #190

Earlier quoted context omitted.

It's not uncommon for outside temperatures in Texas to stay above 80F (27C) until midnight during the summer months. The modern homes there are designed to stay sealed, rather than open windows for ventilation at night. Running AC every ~45 minutes until morning is considered the norm.

Without solar gain you still need less solar power even if the temperature is 80+. Further, you use exponentially more energy to cool as the temperature rises. So, 80f is significantly cheaper than 90f.

Probably quadratically, or even linear, but to the difference.

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#212

Post by ThomPete » Mon, Apr 23, 2018, 7:02 PM UTC

gehsty wrote: post #204

ThomPete wrote: post #193

Earlier quoted context omitted.

The amount of energy needed will increase even though we become better and better at optimizing the individual items power usage. In other words, wind and solar are linear solutions to exponential problems. I have nothing against wind or solar but the idea that wind and solar will be able to solve our energy problems is based on a political mandate, not on science or any realistic evaluation of the energy needs of th…

You need a mix, for now that will include solar, coal, nuclear and wind. I think in the long run this will change to renewable sources + interconnected grids (it’s always sunny / windy / geothermal / waves) somewhere. I’m generally pessimistic on fusion, but then it would cost me my job so I’m bound to be, but is always feels like it’s “50yrs away”

Yes we need a mix but right now we need more (positive) focus on nuclear (and other forms of more exploratory but potentially civilization altering technologies) as it's been almost banned out of existence in the US and Europe.

The current discusison is not based on what's optimal technologically but politically and thats in not small part due to some the unfortunate overreach of parts of the environmental organizations IMO.

I am all for tough legislation but what the current toxic political climate has made it almost impossible to discuss this in any proper matter.

Even me posting on this lead to multiple downvotes. Thats just absurd.

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#213

Post by philipkglass » Mon, Apr 23, 2018, 7:09 PM UTC

Retric wrote: post #206

IpV8 wrote: post #191

Earlier quoted context omitted.

You're going to be closer to $10,000 for that kind of storage. Probably not economical for your use case unless you get good rebates and electricity is expensive where you live. Source: I build home battery backup systems for a living. The types of people buying batteries today live in places where arbitrage is an option (california, hawaii), or where the grid is frequently or always down (puerto rico)... or rich peo…

$10,000 is ~ 50kwh of battery power, that's vastly more than most people are using over a few hours.

As of yet there is nowhere in the world where the installed cost of a 50 kWh hour battery system is only $10,000. I don't think you can even get that much storage for that little money even if you're qualified to install it yourself and are just paying for the hardware. Are you perhaps just looking at wholesale cell costs?

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#214

Post by lostapathy » Mon, Apr 23, 2018, 7:13 PM UTC

nabla9 wrote: post #70

Symmetry wrote: post #51

Earlier quoted context omitted.

If clean energy manages to get cheap enough eventually it will be easier to synthesize simple hydrocarbons out of atmospheric and water than to drill them out of the group and we can end up carbon neutral as a whole. We'll see how cheap midday solar ends up when the price finishes dropping.

The cost of solar stabilizes when the cost is determined by the cost of land, energy storage, electric grid and transfer cost and installation and maintenance. If you get the conversion efficiency to the same level as photosynthesis (30% nominally) the cost of energy could approach the cost of producing biofuels.

Except - lots of current biofuels are thought to be "fossil fuel subsidized" and not that energy positive.

Solar panels also don't wear out soil nutrients, don't need crop rotation, and are probably much less likely to be completely destroyed by weather patterns than the average corn crop grown for biofuels.

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#215

Post by Retric » Mon, Apr 23, 2018, 7:14 PM UTC

lostmsu wrote: post #211

Retric wrote: post #207

Earlier quoted context omitted.

Without solar gain you still need less solar power even if the temperature is 80+. Further, you use exponentially more energy to cool as the temperature rises. So, 80f is significantly cheaper than 90f.

Probably quadratically, or even linear, but to the difference.

Heat gain is linear, but efficiency drops with larger temperate differences. Further, you have to worry about lower relative humidity percentage as you increase temperate differences.

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#216

Post by usefulcat » Mon, Apr 23, 2018, 7:19 PM UTC

rnosov wrote: post #201

hadlock wrote: post #190

Earlier quoted context omitted.

It's not uncommon for outside temperatures in Texas to stay above 80F (27C) until midnight during the summer months. The modern homes there are designed to stay sealed, rather than open windows for ventilation at night. Running AC every ~45 minutes until morning is considered the norm.

Hmm, here in Europe were I live 27C would be considered a rather pleasant temperature. Anyway, sealed houses are not only good for keeping the heat in but also to keep the heat out. If you cool your house sufficiently during the daylight hours that should prevent it from heating up too much even after you stop cooling it (after sunset). But if you absolutely must use active cooling after sunset you might want to get…

Bear in mind that 80F is a typical overnight low in most parts of TX during the summer, particularly in most of the heavily populated areas. Typical high temps during the summer months are mid to upper 90's or higher. Most of these same areas also have relatively high humidity, so it feels even hotter and can take quite a while for the temperature to drop even after the sun sets.

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#217

Post by vidarh » Mon, Apr 23, 2018, 7:40 PM UTC

jimktrains2 wrote: post #168

vidarh wrote: post #135

Earlier quoted context omitted.

There is always demand. The issue is that sometimes demand exceeds supply. Taking away supply has the same net effect as increasing demand. EDIT: with the one caveat of transmission capacity, which certainly can be an issue.

I don't think you're quite getting this. There are times where there is excess demand, even when removing these stores. What's so hard to understand? Prices go negative in the US at times and in Germany more often. That is exactly when something like this would be used: to store that capacity.

The point is that you have a given supply and demand. As long as they are in the right positions in the grid that transmission capacity is not the limiting factor, then you can fix that by reducing supply, or by increasing demand - apart from the issue of transmission those options are equivalent from the point of view of bringing the supply under control. They may not be equivalent in terms of cost, but that is a separate issue.

The original point was that you do not need to have a reservoir to pump from to take advantage of the fast start/stop capability of a hydro plant: Closing the sluice gates and/or bypassing the turbines is sufficient to reduce supply by the generating capacity of the plant.

Having a reservoir as the potential to significantly increase the reduction in excess supply you can handle, that is true, but the lack of that option does not change the benefit of shutting off generating capacity.

Hydro plants have been used to adjust grid supply for as long as they have existed in this way. Not least because with grid prices adjusting dynamically, as long as the reservoir is not full, most hydro plants yield better economic result if they respond to falling prices by letting the reservoir water levels build back up.

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#218

Post by IpV8 » Mon, Apr 23, 2018, 7:49 PM UTC

Retric wrote: post #206

IpV8 wrote: post #191

Earlier quoted context omitted.

You're going to be closer to $10,000 for that kind of storage. Probably not economical for your use case unless you get good rebates and electricity is expensive where you live. Source: I build home battery backup systems for a living. The types of people buying batteries today live in places where arbitrage is an option (california, hawaii), or where the grid is frequently or always down (puerto rico)... or rich peo…

$10,000 is ~ 50kwh of battery power, that's vastly more than most people are using over a few hours.

I was speccing to the 10-15 kwh range. Maybe you can get it for cheaper, but with the use case he described you're talking about a substantial continuous rated power and surge power. How many amps can your $10,000 50 kwh battery push? Also I'm including installation, warranty, etc. It would honestly probably be more than that because he'd likely need a more expensive inverter or 2 inverters to deal with that kind of load (I doubt his AC unit and dryer are DC).

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#219

Post by Retric » Mon, Apr 23, 2018, 7:56 PM UTC

philipkglass wrote: post #213

Retric wrote: post #206

Earlier quoted context omitted.

$10,000 is ~ 50kwh of battery power, that's vastly more than most people are using over a few hours.

As of yet there is nowhere in the world where the installed cost of a 50 kWh hour battery system is only $10,000. I don't think you can even get that much storage for that little money even if you're qualified to install it yourself and are just paying for the hardware. Are you perhaps just looking at wholesale cell costs?

I don't think there is any reason for a home use to install a battery pack without solar power, and with solar power they already need an inverter.

https://www.alibaba.com/product-detail/25kwh-48v-LiFePo4-bat...

Now this is Alibaba so we are talking about dubious quality still it's showing 2,000$ for 25kwh battery pack when buying 2 or more. 50kwh is 2 so that's 4,000$. That's for Lithium iron phosphate battery which should give ~2,000 cycles though they say 3,500.

PS: Grid scale you would want to install the batteries at the solar power plant so again no need for an extra inverter.

Re: How Windmills as Wide as Jumbo Jets Are Making Clean Energy Mainstream

#220

Post by CapitalistCartr » Mon, Apr 23, 2018, 8:01 PM UTC

stcredzero wrote: post #164

coryfklein wrote: post #133

Selling solar back to the grid has one major problem that, fortunately, doesn't plague windmill installations: The Duck Curve [1]. The problem is that peak energy usage now occurs after sunset . So no matter how many solar panels you stack on your home, around 6-7 PM the coal, oil, and gas power plants all have to spin up to their max capacity. Your solar panels are new less likely to _replace_ a coal power plant, al…

* This leads to the power companies naturally feeling rather sour about being forced to credit residents for the power they supply to the grid during low-demand hours. Their costs are staying about the same, but now their revenue stream goes down.* Time to get rid of coal? What the Duck Curve indicates to me, is that California's grad-scale solar really should be located about 6 hours time difference to the west. How…

Operating a power plant in the middle of the World's largest ocean, then transmitting the power 4500+ miles (7000+ km) across that ocean would be one of the World's major engineering undertakings, and vastly more expensive than any current method of generating electricity.