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

How Cheap Can Solar Get?

rameznaam.com

Post reply on HN
Print view View original

51–60 of 138 posts

Re: How Cheap Can Solar Get?

#51

Post by mikekchar »

watchdogtimer wrote: post #44
justaaron wrote: post #25

i live off grid inside of a 500w/h peak footprint. i paid around $1000 for proper German (Schutten) panels, a charge controller suitable for them, 2 110ah "solar batteries" (lead acid usual cheapo old school stuff), and a Xantrex inverter. After nearly 1 year running a fridge, lights, computer, router, & studio monitors, I'm ready to add more battery capacity before the winter (cloudy days) and a small wind turbine.…

Do you always use your MBP connected to a power outlet? If so, try running it until its battery is drained about 50%, then plug it into your inverter and see how much power it draws. My guess is it will draw about 50-60 W. I've been using a pedal-powered generator to power my computer, phone, tablet, and LED lights for the last 5 years and have tested several laptops and other devices using it. I've found that most l…

How much electricity can you generate? Just thinking off the top of my head, I'm a sucky cyclist so can only manage about 150W power output sustained, probably. I'm not sure I could handle more than an hour of stationary biking before I collapse in a puddle of sweat ;-) So that's about 150 WH...

Is that about right (ballpark), or have I missed something? It would probably power my laptop for the day, anyway... It's something to think about (since I love cycling, even stationary ;-) )

Re: How Cheap Can Solar Get?

#52

Post by snsr »

jacquesm wrote: post #37
justaaron wrote: post #25

i live off grid inside of a 500w/h peak footprint. i paid around $1000 for proper German (Schutten) panels, a charge controller suitable for them, 2 110ah "solar batteries" (lead acid usual cheapo old school stuff), and a Xantrex inverter. After nearly 1 year running a fridge, lights, computer, router, & studio monitors, I'm ready to add more battery capacity before the winter (cloudy days) and a small wind turbine.…

If you're up for it I still have my 2500 W windmill here and can't use it so you can have it, the base is damaged (slip rings, tower shaft and tower mount) and you'll need to put up a pretty solid tower. It's a 2.5 meter diameter machine. See: http://jacquesmattheij.com/how-to-build-a-windmill It weighs about 100 Kg and it's currently in storage near the town of Beverwijk in NL. It cost a small fortune to make it and…

What a fantastic project - thanks for documenting and sharing!

Re: How Cheap Can Solar Get?

#53

Post by selimthegrim »

nroets wrote: post #17
RamezNaam wrote: post #7

Hi. I'm the author of this blog post. Happy to answer questions people have, as time allows, on Wednesday. Upcoming posts will look at the future of wind power, the future of energy storage, and what the missing pieces are. If you don't want to wait, you can read my thoughts on energy storage here: http://rameznaam.com/2015/04/14/energy-storage-about-to-get-...

IIRC all the efficient solar cells we currently have contains some rare materials. Once a particular solar technology reaches grid parity, the demand for the relevant rare material will increase, placing a floor under the price of that solar cell. In the case of Moore's Law, a transistor can be any size. By contrast, solar cells absorbs too little energy if they are too thin. TL;DR: There are real physical limitation…

Some so called third generation cells do not necessarily contain rare earths, especially those invoking multiple exciton generation

Re: How Cheap Can Solar Get?

#54

Post by [deleted] »

nroets wrote: post #17
RamezNaam wrote: post #7

Hi. I'm the author of this blog post. Happy to answer questions people have, as time allows, on Wednesday. Upcoming posts will look at the future of wind power, the future of energy storage, and what the missing pieces are. If you don't want to wait, you can read my thoughts on energy storage here: http://rameznaam.com/2015/04/14/energy-storage-about-to-get-...

IIRC all the efficient solar cells we currently have contains some rare materials. Once a particular solar technology reaches grid parity, the demand for the relevant rare material will increase, placing a floor under the price of that solar cell. In the case of Moore's Law, a transistor can be any size. By contrast, solar cells absorbs too little energy if they are too thin. TL;DR: There are real physical limitation…

[deleted]

Re: How Cheap Can Solar Get?

#55

Post by simonbarker87 »

redcalx wrote: post #49
fpgaminer wrote: post #9

If I could install solar today I would, regardless of cost (apartment living prevents it). That may sound crazy, but I theorize that when you consider externalities the cost of grid electricity already far exceeds the cost of solar. It's going to cost humanity a whole lot of money to both survive and fix the damage we're dealing to the environment today. I'd rather pay more now for solar, than pay through the nose la…

Have you factored in the CO2 footprint of solar panels? Producing pure silicon is energy intensive, then there are various metals involved, so you've got mining, refinement, smelting, and bulk transport costs. The panels also have a limited lifetime so you need to think about the disposal or recycling cost in 15-20 years. Pretty sure I've missed a load of costs too.

One thing to remember though is that there is a reasonable level of CO2 extras around generating traditional non-renewable sources (mining, transportation, materials to build the plant, maintenance of machinery etc).

Re: How Cheap Can Solar Get?

#56

Post by selimthegrim »

chm wrote: post #5
1971genocide wrote: post #2

Does anyone know methods for hackers to help and learn more about solar ? It it possible for the mathematically trained to easily immerse and innovate in the industry ? It it possible to manufacture solar cells "in your garage" so to speak ?

My MSc is concerned with a model for simulating molecular photovoltaics. The work I do is a blend of physics, chemistry, maths and programming, in different proportions. I wouldn't say it was "easy to immerse", but complement your skills with physics/chemistry and you could be useful, yes. A Grätzel or dye sensitized solar cell can be easily created in your garage. Look them up on Youtube.

Better models for molecular photovoltaics are sorely needed. Math skills are not unwanted.

Source: I work in the field.

Re: How Cheap Can Solar Get?

#57

Post by jeletonskelly »

redcalx wrote: post #49
fpgaminer wrote: post #9

If I could install solar today I would, regardless of cost (apartment living prevents it). That may sound crazy, but I theorize that when you consider externalities the cost of grid electricity already far exceeds the cost of solar. It's going to cost humanity a whole lot of money to both survive and fix the damage we're dealing to the environment today. I'd rather pay more now for solar, than pay through the nose la…

Have you factored in the CO2 footprint of solar panels? Producing pure silicon is energy intensive, then there are various metals involved, so you've got mining, refinement, smelting, and bulk transport costs. The panels also have a limited lifetime so you need to think about the disposal or recycling cost in 15-20 years. Pretty sure I've missed a load of costs too.

Could it be said that in order to gain the technology and production methods of a cleaner, more efficient energy source we must expend energy from dirty and inferior sources first? It seems to be the case; we go after the low hanging fruit or the fruit that we know we can do something with. If that is the case, then can that be seen as a optimistic outlook for human kind in regards to climate change? That in order for there to be a clean energy future we have to harness the energy sources available to us to get there.

Re: How Cheap Can Solar Get?

#58

Post by brrt »

redcalx wrote: post #49
fpgaminer wrote: post #9

If I could install solar today I would, regardless of cost (apartment living prevents it). That may sound crazy, but I theorize that when you consider externalities the cost of grid electricity already far exceeds the cost of solar. It's going to cost humanity a whole lot of money to both survive and fix the damage we're dealing to the environment today. I'd rather pay more now for solar, than pay through the nose la…

Have you factored in the CO2 footprint of solar panels? Producing pure silicon is energy intensive, then there are various metals involved, so you've got mining, refinement, smelting, and bulk transport costs. The panels also have a limited lifetime so you need to think about the disposal or recycling cost in 15-20 years. Pretty sure I've missed a load of costs too.

This is calculated in energy return on energy invested (EROI). Solar is doing.. ok in that regard: http://rameznaam.com/2015/06/04/whats-the-eroi-of-solar/

The comparable number for fossil fuels (in this case, oil) is 'well to tank efficiency', which amounts to about 25% for oil, if i recall correctly. So 1/4th of energy contained in oil is already spent to bring it to market.

Notably, wind energy has a far more favorable EROI than solar does (currently), but wind power is a relatively limited resource.

Re: How Cheap Can Solar Get?

#60

Post by brrt »

RamezNaam wrote: post #20
Jedd wrote: post #13

Earlier quoted context omitted.

Your post focuses on PVC's - what's the impact of / where does thermal solar fit in with these projections?

It's difficult to say. Solar thermal is not dropping in cost the way that solar PV is. For now, at low penetrations, solar PV is a far better bet. But solar thermal has the advantage of integrated storage. When solar overall is at some reasonably high penetration (say, 10-15%) storage will become important. At that point, it depends on the cost curve of storage technologies. If batteries or other energy storage techn…

There's also, at least on a global-energy-system scale, the issue of efficiency. Solar thermal (I'm thinking of solar towers and the like) can heat a medium to about 300, maybe 400 C, and if I'm not mistaken using a conventional steam turbine that can give you a Carnot efficiency of ~25%, maybe 30%. Real generators engineered today are on the level of 90% efficiency, meaning that a solar thermal plant can - practically - convert ~20% of incident solar energy to electricity. Commercial PV will likely not reach that level of efficiency for years, and there are - probably - good ways to improve thermal efficiency beyond this 20%.

Of course, thermal generators required direct incidence (don't work well on diffuse light), but the long and short of it is that with thermal we (may) need about half the total area we would need for PV. (On the other hand, PV can practically uses space - rooftops - which is inaccessible for thermal.)

Nice blog, by the way :-)

Post reply on HN