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

nytimes.com

221–230 of 285 posts

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

#221
post #192

Anyone familiar with these "bladeless" wind turbines as an alternative to large blades? http://www.vortexbladeless.com/ Based on their marketing (far quieter, 40% more energy) it seems like an interesting option. I know one of the biggest complaints that farmers have is the noise they cause, so they have to be placed far from houses. I'm curious to see if it's mostly fluff or has any potential... but I'm not expert o…

Fluff... dominant factor in potential energy production is area swept out...

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

#222
post #191

Earlier quoted context omitted.

Can you quote costs here? How much will it cost me to install a battery that lets me come home from work, turn on the air conditioner for 3-4 hours, run 2 loads through my washer and dryer (cause I have 3 kids), do a load of dishes, all while running the water heater, lights, etc? Does a single $4,000 power-wall do that? And if it is merely saving me the cost differential from electricity at noon and electricity at 6…

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…

My parents live in a well-to-do suburb of Chicago. After the frequent, repeated power outages in recent years, a battery pack would be considered as an alternative to a generator.

They don't have a generator -- their property does not make one convenient, and they don't currently have medical needs that require constant power.

But when the power goes out in their neighborhood, just walk outside after a few minutes and listen to all the generators.

A lot of U.S. infrastructure is no longer really being adequately maintained. I expect quite a few battery packs will be sold to scenarios like theirs. As long as the power failures don't come to exceed the batteries' power delivery capabilities.

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

#223

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…

>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.

Where are you getting this assumption from?

In hot climates like Arizona, peak energy usage during the summer months is in the afternoon, not the evening. When it's 115 degrees outside, that's when everyone's A/C is running at full capacity. It gets cooler in the evening and A/C usage goes down then.

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

#224
post #140

Earlier quoted context omitted.

California and Hawaii have already implemented price curves that make purchasing solar + storage viable for homeowners. As more states adopt these policies and more homeowners adopt batteries the duck curve can be solved. Also battery storage gives the added benefit of not needing a gas generator when the grid goes down if you have an islanding system!

How does one implement a price curve? By supply & demand, it is just the result of energy production + energy usage. Are you saying that California has somehow made energy scarce during the day or are you talking about price manipulation?

You could skip the price models/curves, and just go with a real-time exchange. Something like NordPool (https://www.nordpoolspot.com/), which trades electricity between UK, Germany, Nordics and Baltics.

Electricity price on the market changes every hour depending on production and consumption. You can trade on it like on any futures market, or as an active participant if you had a large battery or transmission cables. Local utilities here offer "market price + 5% margin" plans to home consumers if you want to take advantage of the lows to adjust your usage.

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

#225

Earlier quoted context omitted.

> Surely you don't run 2 loads through your washer and dryer _EVERY_ day, do you? No, but I need to be able to _any_ day, and honestly for us doing 2 loads a day happens very often - it's not an edge case for us. If you're befuddled as to how that is possible, join the club. As for shifting our day's schedule around electricity rates, good luck bringing that idea up with my wife.

Yeah, but the once a week cases are handled by a connection to the grid, just as at present. The bulk of the necessary time shift is handled by the battery and some other techniques to shift demand, and the rest is balancing contention between households in aggregate, and nudging storage and peaker plants, that is, exactly what currently occurs on the grid. > As for shifting our day's schedule around electricity rate…

>Not everyone would be able to because of noise

Then they should get newer appliances. Modern dishwashers are whisper-quiet, and modern front-loading washers are barely audible for most of the cycle. The energy savings on these newer appliances should more than pay for the initial costs pretty quickly.

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

#226
post #218
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.

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…

His AC unit and dryer may actually be DC, just internally. Modern AC compressor motors are now moving to inverter drive, so incoming alternating current gets turned into DC for the inverter, washers/driers do something similar for the motor. Heating elements are just a resistor, so could run from DC. If I were putting together a system for myself those are the things I would consider, and find ways not to duplicate power inverters throughout the system.

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

#227
post #219

Earlier quoted context omitted.

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…

<$100/kwh for LiFePo4? That seems really hard to believe.

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

#228

Earlier quoted context omitted.

* 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.

Agreed. The ocean is just too deep there. I have a better idea for a megaproject: build a dam across the Strait of Gibraltar, and lower the water level of the Mediterranean. You could get an enormous amount of power from a hydroelectric dam in this location (and later another one near Sicily, after the Mediterranean's level is lowered), plus you'd have a huge amount of new land in the area.

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

#229
post #201

Earlier quoted context omitted.

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.

I've never been to Texas but a Wikipedia article ( https://en.wikipedia.org/wiki/Climate_of_Texas ) suggests that 80F low occurs only in Galveston in July and it's more like 60s and 70s elsewhere. If a humidity is such a problem then you could run dehumidifier during the day and that would lower humidity ( in a sealed house ) overnight.

I mean these temperatures don't strike me as particularly intolerable. I wonder if it's the case of keeping up with Joneses as in "my house is cooler than yours". There are some reports ( https://www.theatlantic.com/magazine/archive/2015/07/saudis-... ) that rich Arabs in Saudi Arabia are running air conditioners at temperatures that require sweaters — even when they go on vacation. Which is really amusing for these of us who come from colder climates.

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

#230

Earlier quoted context omitted.

> Surely you don't run 2 loads through your washer and dryer _EVERY_ day, do you? No, but I need to be able to _any_ day, and honestly for us doing 2 loads a day happens very often - it's not an edge case for us. If you're befuddled as to how that is possible, join the club. As for shifting our day's schedule around electricity rates, good luck bringing that idea up with my wife.

Yeah, but the once a week cases are handled by a connection to the grid, just as at present. The bulk of the necessary time shift is handled by the battery and some other techniques to shift demand, and the rest is balancing contention between households in aggregate, and nudging storage and peaker plants, that is, exactly what currently occurs on the grid. > As for shifting our day's schedule around electricity rate…

As I said, for us it's not an edge case, but the norm. May not be 2 loads every day, but if I had to guess I'd say that happens about every other day.
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