Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Solar Roof

tesla.com

Post reply on HN
Print view View original

341–350 of 455 posts

Re: Solar Roof

#341

Post by 0xcde4c3db »

rhino369 wrote: post #253
ghaff wrote: post #169

Earlier quoted context omitted.

Where I live (Northeast), pretty much the only time where an extended power outage is a serious problem is in the winter. And that's because of losing heat. A Powerwall-like "UPS" that could handle some critical systems (basically my furnace) automatically is interesting. But any solar panels are likely to be under snow and ice. Pretty much the only thing that's really a problem for me in a power outage is losing hea…

How much heat would a powerwall even create? I suspect electric heat would drain those suckers pretty fast. Why doesn't the north east have gas heating?

Gas furnaces typically power their blowers with electricity; the gas is strictly for heat.

Re: Solar Roof

#342

Post by fpgaminer »

lostmsu wrote: post #247
fpgaminer wrote: post #172

Earlier quoted context omitted.

We're paying ~$19.5k for solar panels + installation. After the tax credit, that's $13,650 in cost. We spend ~$960/yr on electricity right now. The solar installation will cover all those needs, plus pay us $711/yr. So we're saving $1,671/yr. Pay off is thus ~8 years. The panels are good for 25 years. That's $28k in savings by the time the warranty runs out. They'll probably last longer. The batteries are a different…

That's much cheaper, than this article. Where is this?

SoCal

Re: Solar Roof

#343

Post by ThomPete »

brandon272 wrote: post #250
robbrown451 wrote: post #236

Earlier quoted context omitted.

Yeah good luck with that plan. ("Honey, if we get a solar roof it will help the planet, but we'll have to put junior in the cheaper preschool to pay for it. Whatya think?")

It's unfortunate that people can't see that junior dealing with the effects of climate change in 30, 40, 50 years could be a lot more devastating to his life than the prestige level of his preschool.

You are not seeing this from its full potential. By going to a better school kid is more likely to get better access to opportunities which then allow them to better survive any potential climate issues. So the parents are thinking rightly about this.

Re: Solar Roof

#344

Post by ThomPete »

omegaworks wrote: post #336
obastani wrote: post #305

Earlier quoted context omitted.

It's a classic case of prisoners' dilemma. Taking your kid out of daycare isn't going to help the planet very much, but could hurt your kid a lot.

Why does there need to be "the best" preschool. Can't we have a society with standards? A society that gives a damn about iniquity?

We have a society with standards. To combination of free enterprise and government is the strongest standard i know of. Have any better structures?

Re: Solar Roof

#345

Post by embro »

RodericDay wrote: post #221
stratigos wrote: post #217

People are thinking way too much about how much this saves them at a personal level. I think people should instead be thinking about how we can save the existence of the entire species, and all other higher order forms of life on earth, rather than focusing on their individual tax breaks, savings, or other trivial concerns. Yes, your cash flow is rendered quite trivial if life on Earth ends. Invest in the Life Econom…

People serious about saving the planet aren't putting solar shingles on their mansions. They're downsizing.

If you are really serious, your goal should be to be net positive, downgrading won't get you there, never.

Re: Solar Roof

#346

Post by fpgaminer »

ch4ch4 wrote: post #185
fpgaminer wrote: post #168

Earlier quoted context omitted.

> Switching from gas to electricity for heating is a bad idea if there's still coal power stations in use You misunderstand. Our solar installation will be expanded to cover the appliances. We'll be 100% off-grid. > Going off grid means you need a lot more batteries We only need 3 PowerWalls to cover all our needs (~1 for our needs now, 3 for when we have electric appliances and a car). That's not "a lot more". > Sha…

Sharing power via net metering is better (for the environment) because there's no conversion loss from charging a battery.

Perhaps I'm not understanding the argument. My interpretation is that y'all want me to dump all my excess power during the day into the grid, to power other homes that don't have panels, instead of charging a battery. And that's somehow better for environment.

But ... when night falls, and I'm not generating any more power, where am I supposed to get power? Do I just live without power every night? And everyone else does too? Cause the only alternative is to burn fossil fuels to power everyone's homes during the night. Fossil fuels being perhaps the most inefficient solar batteries available to us.

And yes, fossil fuels _are_ batteries. Solar batteries in fact. It's just that they have an unimaginably terrible conversion loss, not to mention they're highly destructive to the environment, and take millions of years to charge. If they ever do recharge, which is unlikely, since our planet is not likely to revisit the eras that gave rise to significant quantities of them again.

I think I'll stick with lithium cells with their "conversion loss" of 80%, that take up a small portion of a wall in my house, and last for decades.

Re: Solar Roof

#347

Post by ianai »

salesguy222 wrote: post #279
NamTaf wrote: post #274

Earlier quoted context omitted.

If you ever get to go to Geneva, swing by the CERN exhibit. There's the original fileserver, complete with 'This machine is a server. DO NOT POWER DOWN!!' scrawled on tape stuck over the power button. There's also his paper describing the WWW with the feedback of his manager written across the top: "vague but interesting...". It's kind of comforting to know that my academic and computing experiences thus far are shar…

Haha "vague but interesting". Isn't it amazing how big of a disconnect there is between "people who are capable of identifying/executing on big ideas" (aka Tim and his manager).... and "the projects that businesses/agencies want their employees to do"

Especially when, in hindsight, it's anything but vague.

Re: Solar Roof

#348

Post by danderino »

ianai wrote: post #155
pedrocr wrote: post #44

Earlier quoted context omitted.

>If I put that same $40,000 in an index fund that got the stock market's historical 7% average, and waited 30 years, I'd have $308,000. Are you doing the math all in present dollars? Because the return is 7% after inflation but >10% before. So you'd have >500.000 in 2047 dollars. In this case it's important to do that adjustment because you're doing an investment upfront for payoffs over 30 years so the value of mone…

A 7% yield is an overly optimistic number.

Thats the historical average.

Re: Solar Roof

#349

Post by MR4D »

Tesla has an error somewhere. I checked their website calculator vs their source of Google project sunroof, and Tesla thinks my roof is 5 times bigger, with an electric bill nearly twice as high!

Doing some quick math, I can confirm that Google's number are reasonably close on both, while Tesla's are just plain wrong.

The result is a Tesla roof that would cost roughly $170,000. Worse, that's about half the value of my house!

I know - early days - but, wow, surprised by the estimate!

Re: Solar Roof

#350

Post by ceejayoz »

xj9 wrote: post #338
Retric wrote: post #295

Earlier quoted context omitted.

Does that include the increased risks of nuclear war, new disease vectors etc? Because, while the probable outcome is relatively little impact the butterfly effect means you can get some less predictable results indirectly. Aka migration causes war X which due to _ spiraled into WWIII. Granted the world without global warming could alos end randomly as well so you can just say unknown unknowns are always a risk even…

increased risks of nuclear war you do realize that initiating nuclear war is suicide, right? the u.s. took advantage of the only chance of actually using one because they were the only nuclear power at the time.

> you do realize that initiating nuclear war is suicide, right?

Given there are plenty of suicidal humans, that's not entirely comforting.

Post reply on HN