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Journal Journal: Mars, Ho! Chapter Forty Six

Awake
I woke up about quarter after seven, and Destiny was already up and had coffee started. "Hungry?" She asked.
"Yeah, I am. Did we even eat dinner last night? Did you tell the robots to start breakfast?"
"No, I wanted to try something new for breakfast and wanted to see what you wanted to eat first. You know I'm a history buff, well, I found a really old recipe in the computer called a

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Journal Journal: Mars, Ho! Chapter Forty Five

Injury
We both woke up around seven, still cuddled up on the couch. We'd been asleep for fifteen hours on that thing. We cuddled a little while more, then Destiny started coffee while I took care of the ship's air and corrected the course, since I was sleeping when the generator came back online.
We took another shower together after drinking a little coffee and she told the cook to make pancakes and sausage, and we watche

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Journal Journal: Mars, Ho! Chapter Forty Four

Nitrous
I pulled out my fone and called the fleet commander who I was amazingly boss of and told him about our little power problem, then asked the computer what the robots were doing about repairs. Or tried to, anyway.
"Computer, what is the, uh... status of..." and the God damned machine interrupted me, of course. Who programs this junk anyway?
"All cargo unconscious except specimen in com

Comment Re:Feh (Score 1) 10

It IS about race, you stupid fucking racist. Brown wasn't a thug, he had never been in trouble with the law and was enrolled in college to learn engineering.

The protests started peaceful, and only turned into rioting when the idiotic, racist Ferguson police acted like the racist morons they are.

People (and I use that word grudgingly) like you are the problem. I'm a white man who grew up in the St Louis area, and can tell you from experience that Missouri is indeed the most racist state in the union.

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Journal Journal: Mars, Ho! Chapter Forty Three

Monsters
"Hold on, Destiny," Tammy said, "we're still in trouble."
I got it. Finally, even being so tired that my brain wasn't working right. God, what a dumbass I was! I really needed some sleep, but I wasn't going to get any for a while. "Computer, lock all doors," I said. "She's right, Destiny, We're in trouble. I finally get it. She left them short of drops and told them the pirates stole them. They're not even human a

Comment Re:Some can be done - and is. Most is bull. (Score 1) 442

Sounds like you've got a much higher essential demand than what I figured on - desalinization?

Sorry for the delayed reply but I was re-running the numbers :)

When I was doing the calcs originally, I was really only interested in staving off power outages like we had with Sandy, which was about two weeks worth... not being completely off-grid. So focusing on hurricane season as a baseline, a 7kW system with 6kWh of storage would provide essentially unlimited off-grid capability from April through December *if* I managed my power consumption to essentials with just a little bit of creature comfort.

The winter months, however, result in a deep, DEEP deficit. I'd need 10kW of PV with 80 kWh of storage to be completely off-grid based on PVWatts data (with no power management). Of course, that's still relying only on Solar, and being completely off-grid was never the intention.

I don't pertain my own home is a good proxy for a regional or national grid, though ;)
=Smidge=

Comment Re:Drop solar heat for direct conversion (Score 1) 521

Except you can not exceed the solar power that hits the surface of the planet from the sun.

...which is a hell of a lot of energy. Collectively it's several orders of magnitude more than we as a species could ever reasonably harness, let alone use.

You could, for example, generate more kWh of electricity by putting 15% nominal efficiency PV systems on the roofs of ONLY single-family homes in the US, based on 2010 census data (67% of 130 million residences being single-family homes, with an average size of 2,400 sq.ft.).

In other words, we could hypothetically generate more than 100% of the electricity we need in 7800 square miles - about 5 Rhode Islands. That's at 15% nominal efficiency, assuming only 4 hours per day of operation. In other words, an extremely conservative value.

Just putting things into perspective.
=Smidge=

Comment Re:Some can be done - and is. Most is bull. (Score 1) 442

What resources did you use to model these inputs? PVWatts I can understand for solar, but I'm not aware of any similar tools for wind and micro-hydro. Genuinely interested in what your data sources were.

Not that I'm yet convinced your model is applicable to a regional or national scale grid. Did you account for geographical diversity? Availability of these resources spread out over maybe 200-300 mile radius?

Also, peak demand of 5kW for 3 hours? My home has all electric appliances and I rarely, if ever, hit that... including the 3kW clothes dryer. This observation is neither here nor there, but that just strikes me as a high value.

To put things into perspective, I've been collecting minute-by-minute data for my own home's electrical usage (Got one of these things) and based on incomplete-at-the-time data it was looking like I could get away completely off-grid with a 6-7kW PV system and about 6kWH of storage. Less if I was smarter about how and when I used that power. Maybe your data doesn't have good enough resolution to really optimize the system.
=Smidge=

Comment Re:Estimates (Score 2) 521

1. Solar Thermal plants are built in the desert because that's where they have the most ideal operating conditions. The fact that there are more birds in forests than deserts is completely irrelevant because they don't build concentrating solar plants in forests.

2. We would expect the casualties to scale roughly with the number of plants, so is you had 1,000 such plants, that would be 1,000x the casualties. Still a drop in the bucket compared to the billions of birds killed by feral cats every year in North America.

3. You are right, of course, however you have to consider a cost-benefit as well. The cost of preventing bird deaths from not building concentrating solar plants (both monetarily and environmentally) versus, say, the cost of preventing bird deaths by doing something about the cat population. If saving the birds is the priority, then perhaps your dollar would be better spent on programs to reduce feral cat populations than preventing solar thermal plants from being built.

=Smidge=

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Journal Journal: Mars, Ho! Chapter Forty Two

Boarded!
Me and Bill hauled ass out of there towards Mars as fast as his crippled boat would take him. I did another inspection because first, I hadn't done a full inspection yet that day, second because I'd pushed her pretty hard, and third because I sure didn’t need any new surprises. We were at a third gravity because of Bill, and he was having a hard time keeping up. A third gravity? On batteries? I need to have him teach me some of that nerd

Comment Re:Some can be done - and is. Most is bull. (Score 1) 442

A single home isn't a very good proxy for a regional or even national scale grid.

With your house example, the only options are solar and generator. In reality you would have more than these two options. For example, add wind to the mix. You can argue that it's not 100% but it will cover a lot of run time at night, saving you battery capacity and reducing the required over-sizing of your PV system. Perhaps instead of 400% oversizing on PV, you only need 200% PV+Wind oversize.

Now add in something else... biogas perhaps. That covers you a little bit more and you can again reduce your oversizing.

Now add geothermal, hydro, solar-thermal (which works at night), and you start to easily fill in the gaps.

The US had 1,153 billion watts of generating capacity as of 2011 (Nameplate ratings, spreadsheet) and used ~3,797 billion kilowatthours that year. Naively we can say that if all our powerplants ran at 100% nameplate capacity, we could generate an entire year's worth of electrical energy in just about 3300 hours, or about 4 months... giving us a roughly 300% oversize on our electrical generating capacity *now*.

The key, of course, is that none of those plants are operating 24/7/365, and rarely are any of them operating at peak capacity.
=Smidge=

Comment Re:There is a big construction boom in Germany... (Score 1) 442

I'd also point out that Germany's accelerated decommissioning of nuclear power plants (all shutdown in 8 years) has a lot more to do with the coal plants than the increase in renewables.

Doesn't make sense: Coal power has actually decreased since 2000 when it was first decided that Germany should ween themselves off of Nuclear power, and the slight increase in coal power in the past two years is only a fraction of retired nuclear capacity, both in total and as a percent of total generation.

Germany's renewable energy push is what's filling that gap. If it wasn't for the nuclear phase-out, they'd probably have lost a third of their coal plants instead.
=Smidge=

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