Follow Slashdot blog updates by subscribing to our blog RSS feed

 



Forgot your password?
typodupeerror

Slashdot videos: Now with more Slashdot!

  • View

  • Discuss

  • Share

We've improved Slashdot's video section; now you can view our video interviews, product close-ups and site visits with all the usual Slashdot options to comment, share, etc. No more walled garden! It's a work in progress -- we hope you'll check it out (Learn more about the recent updates).

×

Comment: Re:Help me out here a little... (Score 1) 267

by Ferretman (#49506393) Attached to: Utilities Battle Homeowners Over Solar Power
Not sure how you get from nationalizing energy production to exploring space....?

In either event if you knew anything about Cold War history you'd know that the Russians primarily operated their space program as a way to shake out various engineering issues for their ballistic missiles--putting a person into space was just a nice touch and gave them bonus propaganda points. And to further push a bit nobody said government couldn't do some things well, just that they generally can't do them as well as private industry.

But that's off the subject, which was privatiziation vs. nationalization of power production. How do you avoid the obvious lessons learned over the past few decades that point against such nationalisation? Are you saying it would work here in the United States for same reason where it hasn't in other places? What specifically makes you think that?

Do you include companies such as Solar City and what Elon Musk is doing with his Tesla power packs for the home in this nationalization? Why or why not?

Ferret

Comment: Re:The power should be cached in the community (Score 2) 267

by Ferretman (#49505943) Attached to: Utilities Battle Homeowners Over Solar Power

A small lead acid bank capable of driving a house for an evening isn't that expensive.

Please define "not that expensive".

Eight of these for example would run you just about $3000 (I chose 8 to get you to a 48V system, the common configuration for off-grid systems these days). I include shipping but not the wiring and interconnects and such to make them work for you:

http://www.wholesalesolar.com/...

A lead-acid system shouldn't be discharged more than around 20% in order to avoid longer term damage; you can discharge them more deeply but you'll shorten their life significantly:

http://www.solar-electric.com/... of Batteries

Scroll down to the "Cycles vs. Lifespan" section and click on that chart. It's amazing.

So if you are likely to use half of your storage (~225AH for those selected) then a single set of batts would be discharged 50% in normal use. At that rate the batts will last you around 1000 charge/discharge cycles, so a bit less than 3 years if it's every day. If you want them to only be discharged 75% (moves you up the lifetime curve to 2000 charge/discharge cycles or around 5.8 years) it'll cost you double the price above, or around $6K. And quite honestly 225AH is a very shallow system....we're not talking about much being on overnight here. You definitely couldn't consider running a microwave--you'd tap that puppy right out.

I'm leaving out the equipment costs and such; charge controllers to dump power into the batteries and an inverter to take power out will add around $5K more.

I love the idea of as many folks as possible having back up and/or being off-grid entirely (I am) but it ain't cheap. I did it because I had no other choice here; the house is 5 miles away from the nearest power line.

Ferret

Comment: Re:Solar is here to stay (Score 1) 267

by Ferretman (#49505843) Attached to: Utilities Battle Homeowners Over Solar Power

Battery cost has dropped by 94% in 20 years.

I'm sorry but that's uninformed nonsense. Battery prices have barely budged in the last 5 years--I know, I've got an off-grid system that needs batteries for off-hours and bad weather storage.

The biggest single advancement batteries have made in the last 20 years was to put carrying straps on the sides of the things so they're a bit easier to handle.

Ferret

Comment: Re:Help me out here a little... (Score 1) 267

by Ferretman (#49505809) Attached to: Utilities Battle Homeowners Over Solar Power

The grid needs to be privatised. Electricity is something we all need, like roads and other basic infrastructure. It should work for the general good, not profit.

Um, I think you mean nationalized in this context. You want it to be owned by the government for the "general good", whereas privatizing it would mean it was run for a profit.

I disagree completely of course--it was nationalized in the Soviet Union and it is nationalized in places like Venezuala and Cuba. Power don't work so good there.

Ferret

Comment: Re:Ok.... Here's the thing, though ..... (Score 1) 267

by Ferretman (#49505401) Attached to: Utilities Battle Homeowners Over Solar Power
Good post; thank you. I think many who champion renewables don't understand the issues involved in spinning up/shutting down the big power plants, and what that means for grid stability.

I'd tend to agree that we want to see more smaller scale power plants and I think we will over time, though it's going to be difficult. The industry has spent a lot of time and effort consolidating everything into larger facilities mostly out of sight, so to move smaller facilities out into the suburbs runs into all kinds of problems. You'll have the NIMBY folks of course no matter what kind of plant it is. There will be infrastructure rebuilds and re-routes that will disrupt people and cause their own set of problems. A big solar field will probably have less opposition generally, but of course those require a lot of room--which can be hard to find near a suburb.

Concur completely about going LED where it's possible. I live 100% off-grid and so watch every watt that the house uses like a hawk. Recently I just swapped out all of my halogen track lights to LEDs, dropping energy use (if they were all on at once) from 2000W to 320W--an amazing difference. These track lights were the last remaining "hard" lights to replace as they're a GU-10 form factor and there aren't a lot of that size LEDs out there.

Now I can focus on the rest of the house with more "conventional" bulbs. Everything else in the house is CFL; there are 255 lights in all inside and I've managed to covert 125 of those to LED so far. It'll be a project I probably won't finish for a year (LEDs are pricey) but when I'm done I'll use a lot less power for my lighting.

Small steps!

Ferret

Comment: Re:My Off Grid Experience (Score 1) 279

by Ferretman (#49456247) Attached to: The Myth of Going Off the Power Grid
Not really sure if that's in response to me or not...

If it is then the simple answer is I have a fairly large house and I never intended it to be the "typical off-grid house". This is a modern house with all manner of modern stuff. I use between 600W and 1000W per hour most hours, a little more if things all come on at the same time or something. My current battery stack simply can't handle anywhere near that much (it really couldn't even when it was new, much less so now that the batts have been damaged and inadvertently abused). My next battery stack will be able to power me for three days if I don't get much or any sunlight which will more than handle all but the darkest stretches.

LED bulbs will only get you so far--you've still got well pumps and microwave ovens and circulation pumps that will do their thing from time to time. Even the Grundfos pumps (which are what I have) still use power.

Ferret

Comment: Re:i live off the grid completely... no other opti (Score 1) 279

by Ferretman (#49455753) Attached to: The Myth of Going Off the Power Grid
One of the first things I did once we moved in was to ban all electric space heaters--they all went to the ARC. As you say they're immense draws and will take a battery stack down faster than nearly anything.

Now, since then I've relented slightly and picked up a couple of small (200W) heaters off of Amazon for my mother. Even though she keeps her apartment area at Bermuda-like levels (~85 degrees F) she still can get cold when she first gets up on a winter morning, so one of these under her blanket over the easy chair does wonders. But that's basically my only concession there.

I did also move all of my computing to a laptop but that was mostly because the desktop died and I've decided to redo my computer room (basically a third story tower room). But by the time I have that up and running I'll have the new battery stack and won't be as worried about it.

Ferret

Comment: Re:My Off Grid Experience (Score 1) 279

by Ferretman (#49455689) Attached to: The Myth of Going Off the Power Grid
Wow that's amazing! He actually gets enough methane to do this? Remarkable.....I definitely envy him on that.

My batteries are a quite frustrating situation. My solar guy (who really did mean well) just plain undersized the system. To make it worse he knew I didn't want to bother with ongoing maintenance, so he selected Gel batteries for the system. Gel batteries are quite fine but meant more for things like remote towers and the like, with little deep discharge. Given that my system was heavily discharging it only took a year or so to see a definite degradation of their capacity.

The next batts will be AGM (Absorbed Glass Mat). These also don't require any maintenance but are both more forgiving of the occasional deep discharge and not subject to overcharge (which in Gel batts causes big burned "bubbles" in the Gel).

Your brother is doing remarkably I dare say. I'd have a lot of trouble with bears if I did that, but it's working for him and that's awesome! Tell him he's got a fan here in Colorado!

Ferret

Comment: Re:My Off Grid Experience (Score 1) 279

by Ferretman (#49455677) Attached to: The Myth of Going Off the Power Grid

Finally, someone on here who gets it. The independence of being off-grid is just, well, incomparable to anything else - especially when the grid here was out for 3 days in 2011 after a cyclone. All my grid-connected neighbours had to throw out the contents of their freezers and refrigerators, and they didn't have flushing toilets (no electricity=no water pumps. They had to put buckets out in the rain to catch water).

YES! That's precisely right....I have power and utilities and lights and cable and internet and everything even when the local power grid is out entirely. It's totally awesome.

I haven't given much thought to a dual battery system, no. While I have two charge controllers it would at least require me to pick up another Mate in order to monitor/control an entirely separate bank, and I don't usually have a problem with the batteries tapping out to full (lots of panels) anyway. I just don't frick'in have enough batteries really.

I'm sorry, I don't know anything about converting generators. I picked up a relatively small propane generator from Outback called the Ecogen....it's a great little puppy and made especially for off-grid situations. Very pleased with it; it's holding up well and should get me through to the new battery stack! :)

Ferret

Comment: My Off Grid Experience (Score 5, Interesting) 279

by Ferretman (#49451271) Attached to: The Myth of Going Off the Power Grid
I've been fortunate enough to live entirely (100%) off-grid for several years now. When I went to build my house we quickly determined that it wasn't worth it to have power brought back to the house site (I'm 5 miles up in the mountains) and after looking at wind for a bit I went with a solar setup. It's been an interesting experience, and reading the article I can't really say I agree with the author on most points.

I have a 36 panel system that theoretically can create ~40kwh/day on the average day. I have 20 batteries (used to be 24) to cover overnight and overcast/bad weather storage.

First off there's no question that I don't have anywhere near enough batteries. My solar guy used a variety of online calculators to figure out the size and needed and both underestimated my requirements and overestimated the amount of daily discharge the system could handle. As a result we bought a vastly undersized battery system (~1350AH when it was new, more like 750AH now) that we ended up discharging around 75% nearly every night. This is turn is a deadly drain on your batteries and drew down my system sharply to its current capabilities. My own back-of-the-envelope calculations show that I need a system more like 3000AH in capacity to properly power the whole house for a couple of days (if needed). My propane backup generator gets run far more than it ought right now.

Leaving that annoyance to one side though, being off-grid and responsible for my own power (and water; I have an excellent well) is nothing short of awesome! It's my power! I can do what I want, run what I want, and the only thing I have to worry about is what my supply is (when it's at night).

Mind you I've done all kinds of things to be more efficient of course. I am in an ongoing process of replacing all of my CFLs and the handful of incandescents still around with LEDs as I find LEDs that are both price-rational and workable for the task. I just replaced 42 halogen track lights with some excellent LEDs I tracked down from a company named Torchstar and that made a huge difference--I basically hadn't used those tracks at all since we built the house since they were so energy expensive. The house itself is an ICF (Insulated Concrete Form) house and very efficient (13" thick walls), with the entire house heated with radiant heat as opposed to a more typical forced air system. Over the years I've learned to take advantage of a strong sunlight day and run dishwashers and the clothes when the sun is out.

My biggest intermediate goal is to replace the battery stack with something more appropriate. There are several high-amp setups out there that I should be able to make work and I hope to do so next spring (I'm going to be driven to this anyway by the slow death of my current stack). Longer term I'd like to add even more panels until I'm up to 54, not so much for added storage (there's only so much you can put in the batteries and I should have that covered) but to increase the surface area of collection during a cloudy day (the panels will make power even in overcast, so more in that case is better). I think my inverters (two of them, 4000W each) are sized appropriately, though I'll have to add another charge controller when the new panels go in. I just built a new shed to house all of the batteries (it's also ICF) and will be rigging it with a solar heating system this summer; this will keep the batteries warm and toasty during the harsh winters. Even longer term (years), I want to enclose the upstairs deck with a greenhouse, which would help make me more self-sufficient food wise.

I wouldn't change it for the world, honestly....being utterly independent is just a different but good feeling.

If anybody has questions, just ask!

Ferret

Dynamically binding, you realize the magic. Statically binding, you see only the hierarchy.

Working...