Project Sunroof • Hacker News Board

Re: Project Sunroof

#171

Post by secabeen » Mon, Aug 17, 2015, 9:38 PM UTC

birken wrote: post #161

bmelton wrote: post #147

Earlier quoted context omitted.

Except that, as pointed out above, the utilities only pay the wholesale rate for the electricity they buy back from you, and sell the overage to your neighbors for full price. Meanwhile, you're likely losing money selling your peak day electricity for 5 cents and buying it back for 15.

At least with PG&E, my understanding was that those rates only applied to a net over-production over a long period of time (I believe over the course of a year). As long as your power bill is not negative, any over-production during high value times of the day is sold at the market rate and offsets low value electricity you buy at night. This is important with solar system sizing, because not only don't you want to b…

This is correct. Under Net-Metering policies in effect in California for systems installed now, you get reimbursed at full retail rates for every kWh you produce and export to the grid up to the level you import from the grid when solar is insufficient to need (at night, etc.) The wholesale rate is only for exported power generated beyond imported use.

Re: Project Sunroof

#172

Post by aidenn0 » Mon, Aug 17, 2015, 9:38 PM UTC

mbostleman wrote: post #132

kuschku wrote: post #129

Earlier quoted context omitted.

Well, look at the subsidies for the existing energy companies. Nuclear companies get the waste handling for free, if they break regulations, often the government pays the bill... Coal companies never pay for the damages to the environment their huge quarries do... Subsidies for solar are just one part of it. If you take these subsidies that you give the energy companies, and add them as tax to the electricity price,…

If what you're saying is correct, if subsidies were removed across the board taxes would go down, energy costs would go up and solar would take off and replace coal because it would be the (real) best deal.

Even fairly conservative estimates of the negative externalities of coal do in fact indicate this for daytime loads.

Re: Project Sunroof

#173

Post by andyl » Mon, Aug 17, 2015, 9:40 PM UTC

calciphus wrote: post #166

andyl wrote: post #118

Earlier quoted context omitted.

To me, what makes it powerful is the ubiquity - the 'full take' ness of it all. Sure the app is solar-related data, just for a few regions. But could include whatever data Google chooses, expanded to the whole world, for whatever audience Google chooses. I've worked with aerial surveillance systems, the types used on police choppers. Put the crosshairs of the flir camera on a house and it will tell you all kinds of s…

But if the data is already public, surely making it more widely available devalues it as a means of control or coercion? You can blackmail me if you know something no one else does. You can't if you know something everyone else does. Services like this fix asymmetric access to information. They're not revealing anything new.

Normal citizens do not have the ability to perform data-fusion like Google or a Government Agency. Services like Sunroof give just a tiny window into what they know about you. Hardly anything could be more asymmetric.

I believe the potential for abuse exists. Everything is fine now (here in California). But when the next crisis comes, data-fusion can be a powerful tool for authoritarians to control their opponents and suppress dissent.

Re: Project Sunroof

#174

Post by marcosdumay » Mon, Aug 17, 2015, 9:41 PM UTC

VLM wrote: post #92

thrownaway2424 wrote: post #83

Earlier quoted context omitted.

The 3-4c wholesale rate is for base power (giant infrastructure generators, hydroelectric dams and such things), but solar knocks the top off the mid-day demand curve, at which time PG&E is paying much more for "peaker" power generation. But they don't have to pay you the peaker rate, they pay you the baseline rate. Anyway, to my mind, any system in which current comes out of your PV installation at 3 cents and flows…

Something I worry about with solar is once power is psychologically "free" I'll be tempted to set the thermostat down to 65F or whatever, and end up paying full rate when clouds blow by. I think it would be difficult not to increase power use once its free. I'm not talking about explicitly leaving stuff on for fun, but more like "well, power is free, so I guess I can afford a tropical reef tank instead of a plain fis…

Your array of inexpensive resistors will heat your house just as much (or probably much less) than a window would.

But you can use heat pumps, and you can do deep storage of summer heat, for use at winter (no idea about how well it works at your place). Both are very efficient.

Anyway, if your marginal price for electricity is zero, and the marginal externalities are also zero, there's not much problem in using it.

Re: Project Sunroof

#175

Post by aidenn0 » Mon, Aug 17, 2015, 9:42 PM UTC

mikepurvis wrote: post #128

protomyth wrote: post #79

Earlier quoted context omitted.

> Perhaps it should link to a solar installer, and a lumber jack :-) Let's not be cutting down the carbon dioxide remover when we're trying to go eco-friendly. :)

Any gains from PV would be washed away by increased air conditioner usage. If you have a house in shade, be very happy.

Energy wise, I wish my lot were less shady. I spend 0kWh per year on AC (days over 90 are rare), but heating is another matter.

Which reminds me. If anyone knows a good way to retrofit an house with no ducting and no natural gas for any form of efficient heating, let me know.

Re: Project Sunroof

#176

Post by marcosdumay » Mon, Aug 17, 2015, 9:42 PM UTC

jsprogrammer wrote: post #78

thrownaway2424 wrote: post #73

Earlier quoted context omitted.

Solar power systems don't necessarily come with batteries but a decent installation company should be able to propose and implement an integrated system. The Tesla battery pack is an example of some recent innovation in that area. You can sell power into the grid but PG&E only has to pay you wholesale rates, 3-4 cents per kwh, not what they are charging you to take the same amount of energy out, which is 34 cents per…

Is there no real solar power market then? If your local utility is a monopoly then you basically have to accept whatever the utility wants to pay you (even far below 'market' rate). You have no power to negotiate, only capitulate or try to get the local regulator to enforce fair trade.

Well, you can go buy a battery.

Re: Project Sunroof

#177

Post by ZeroGravitas » Mon, Aug 17, 2015, 9:47 PM UTC

mbostleman wrote: post #139

tstactplsignore wrote: post #134

Earlier quoted context omitted.

This is an argument detached from two realities: (1) that fossil fuels receive enormous subsidies in the US and worldwide, and (2) that there is an enormous impact of CO2 on global climate, health, and ecosystems (not to mention the local environmental and health impacts of coal mining and fracking). When accounting for these costs, it becomes increasingly dishonest to claim that fossil fuels are cheaper than renewab…

That may or may not be the case, but the claims that these systems are "cheaper" prey on economic ignorance.

The reality is the reverse of what you state.

The people who think our current use of coal is "cheaper" are economically ignorant, as it generates many dollars of externalities in pollution that affect health. That cost is born by taxpayers, so by avoiding it, the country saves money and in return passes some on to the person with solar on their roof.

I personally would prefer the more direct and elegant solution of a revenue neutral carbon (& GHG) tax, rather than the current tangle of overlapping regulations, but the immediate result would be the same, people with solar installations would be better off than those who didn't since they'd not need to pay the cost of carbon for electricity they generate themselves.

Re: Project Sunroof

#178

Post by listic » Mon, Aug 17, 2015, 10:14 PM UTC

Why are so many people in the USA live in individual houses rather than condominiums (apartments)? The latter is just so much more economical.

Re: Project Sunroof

#179

Post by ZeroGravitas » Mon, Aug 17, 2015, 10:15 PM UTC

thrownaway2424 wrote: post #155

JshWright wrote: post #121

Earlier quoted context omitted.

Heating your house _directly_ with electricity is inefficient. Using that electricity to run a heat pump can be very efficient (assuming you have a large enough heat reservoir (e.g. a few hundred feet of pipe buried underground))

How can heating your house with electricity be less than 100% efficient?

If that electrical energy was generated from gas, then it's often more efficient to burn the gas directly for heat. So depends when you take as the starting point for 100%

Re: Project Sunroof

#180

Post by Someone » Mon, Aug 17, 2015, 10:24 PM UTC

d215 wrote: post #38

http://www.zonatlas.nl granted it is in dutch and made by a completely boring governmental institution. OTH it's made with openstreetmap.

And http://www.zonnekaart.nl, which links to similar initiatives, such as zonnekaart.nl (gives detailed information about what parts of roofs are useful) and http://www.zonnig.haaglanden.nl (cool color scheme)