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Are Hybrid Solar/Grid Houses Practical?
Controlio asks: "With the continuing power crisis and the announcement of major power rate hikes, I figure now is an excellent time to pose this question. Instead of pay these inflated prices for power, I'd like to sink my money into a long-term solution. Cutting myself off from the power grid isn't practical, as I use too much power periodically to be 'solar-only'. But how practical is adding solar for either power redundancy (in case of a blackout) or as supplemental power? Redundancy would be nice, but being supplemental would involve using solar power as my primary power when it's available (and I hear tell that you CAN have negative electric bills if you produce more than you use). Do the costs/advantages for either provide enough incentive to be worth investing in? How would one go about creating a hybrid house? And finally, of course, which is cheaper? Investing in expensive solar paneling, or paying the outrageous charges the power company wants?"
Solar panels are still relatively inefficient. IIRC they only convert about 5-10% of the light hitting them to electricity.
Another way to reduce power bills would be to use solar power to "preheat" water by a few degrees and then heating it up conventionally to the required temperature.
If it's electricity you're after, a "solar furnace" might be better. You get a nice parabolic mirror and pass cold water across the focus. The focused light heats up the water and makes steam which can be used to drive a turbine, driving a generator. You can also use the heat directly to melt metals. (Sunlight is at a temperature of 6500K)
I'm out of my tree just now but please feel free to leave a banana.
The company that makes these is Atlantis Energy, and you can check it out here:
HTTP://WWW.ATLANTISENERGY.COM/ATL/default.asp
Is much higher than you would think. Solar is often singled out by skeptics like this because the panels DO require a large amount of energy to make. However, more common energy sources suffer from similar problems. It takes a good deal of energy to search, drill, ship, refine, ship again, and distribute gasoline, for example. Do you think driving all of those trucks around the country loaded down with tons and tons of oil, running refineries, searching out new drilling locations, setting up drilling equipment, and cutting through the rock is energy efficient?
According to this article, the actual cost of gasoline once the tax breaks the oil companies are given are added back in is around $15.14 per gallon. Ouch.
Nearly every source of energy suffers loss in production like this. If you're going to apply that standard to solar, apply it to other sources as well.
If it's a new house, meaning you haven't broken ground yet and you're still talking to the architect, then you can make the energy savings work. If it's an existing house, then there's quickly diminishing returns.
The Canadians experimented years ago with super-insulated houses located up on Hudson Bay. When I say superinsulated, I mean four-foot thick insulated walls with foot-thick panels that closed over windows at night. It wound up being that the body heat from the occupants almost heated the house. If you cooked, even in the dead of winter, you had to open a window. Some of the solar heating panels were disconnected because it actually overheated the house. If you insulated a Florida or Arizona house that much, you could keep it nice and cold inside. (Insulation doesn't just keep heat in.)
If it's solar power you want, well, that kinda works. You can live off it, but it takes a lifestyle change, and some rewiring. No distributed.net cracking for you, and you'll need to get rid of all those appliances (microwave, stove, VCR) that use power when they're not on (those little clocks and indicator lights add up). The Chicago Tribune ran an article a few months ago about apartment dwellers, in urban Chicago, who had gone solar. It can be done, it costs money, and a lifestyle change is mandatory. No blow-drying your hair, no clothes dryer, no electric oven.
Wind works pretty well, depending upon where you live, and depending upon zoning laws (neighbors may not want one looming over everything). There's some concern that wind power kills birds, but since they tend to place those flailing blades in prime bird habitat (open grassy fields), then it may not be a causal relationship. All the old windmills and wind-powered water pumps don't kill birds, so someone needs to get a big grant and do more research. It might be habitat/proximity, and it might be blade design. Maybe noisier blades would help.
What alternative energy for an existing home does do is cut down peak use, and perhaps spin your meter backwards sometimes. There's tax breaks for alternative energy sources, but basically be prepared to write the whole expense of installation off, and consider it paying off Mom Nature's bills. Figure $10-20k to get anything significant going. You'll need a big bank of batteries to store that peak power to consume during off times (like nighttime), or just spin the meter backwards and sell it to the local utility.
If you're lucky enough to have a running stream nearby, there are companies that sell mini-hydro devices. It's not a small dam, but just a small turbine that a head of water spins.
Try http://www.homepower.com as a great starting point.
Contrary to Bush's pathetic energy plan, the real solution is (in order), Lifestyle change, convervation, and consumption limiters (insulation, efficiency changes [better appliances]). Drilling for Alaskan oil won't create one watt of power for California since California doesn't have any commerical power plants that use Petrol as a power source. They may augment power generation with these things, but it's not really what you build a power plant from.
This place has been featured on the History Channel and HGTV. Okay, it's in Maine. Maine is a long way from California. In this case, heating via solar is a goal (but not exclusively), just perhaps more so than in a California home application.
- www.solarhouse.com is the site.
Yes, in some cases, he gets a check from the power company instead of a bill. It's do-able. He's also installed an inverter and battery system for power in the event of grid blackout.I'd wonder, carefully considering de-regulation, if you can choose which power company to sell your surplus to...? It might be something to consider, as I have seen advertising for power generators in California with different goals (environmentally friendly & socially conscious vs. low cost & raping the land, etc...)
He speaks directly to California residents in several places, and has a point that I envy.
(No such luck in my home state, dammit.)
(Final "grain-of-salt" note -- I don't agree with some of the cost numbers he quotes for non-solar houses. $400 worth of heating oil used in just 28 days??? They must have been heating all of southern Maine! Perhaps they had a 500 gallon tank topped off, but I can easily make that much heating oil last for 6 months... and that includes hot water, too. Yes, my place is smaller, but I have horribly leaky windows, and not-that-great insulation... I still don't use that much oil.)
"...America's great minds of today, teaching America's great minds of tomorrow. Poor bastards." -- A Beautiful Min
By parents have two solar panels on their house (Phoenix). These panels power their water heater for them. The water heater is not on a schedule - the water is always being heated. Their house is about 2,000 square feet. The entire house has vaulted ceilings.
My house has no solar panels and is about 1,500 square feet. I have only two rooms that are vaulted (living room and master bedroom). I'm also in Phoenix.
Our electricity bills are the exact same.
What they save in heating the water with solar power allows them to cool 500+ more square feet. I estimate that the water heater represents about 1/4 to a 1/3 of my electricity bill.
There's a great book on doing all of this stuff called _The Independant Home_. Unfortunately, it seems to be out of print, as I can't find it at any of the major book outlets online. However, Amazon (I know, I hate their politics too, but they have a useful search engine) has a bunch of books on building renewable energy into your house. I don't know how good any of them are, but it's a place to start.
I took a class in renewable energy back in college, which is where I picked up the book I was talking about. At the time ('96) it was still hard to get a lot of "modern conveniences" like TVs bigger than 8", or non-portable stereos that are 12V friendly. And forget about appliances like dishwashers, washing machines, and clothes dryers. Now if you make your battery storage array big enough, and also include wind power for the cloudy days, then with the right inverters you should be able to run a lot of your stuff "off-grid". However as you point out, unless you are willing to make substantial lifestyle changes and invest a buttload of money up front, you are never going to reach self-suffience.
What it really comes down to is how much money and work do you want to invest in this? If you have enough land, and you do a combo system (PhotoVoltaic and Wind let's say) then you can probably generate enough power to not have to worry about rolling blackouts, at least as long as you're smart about it and don't run your oven, 6 microwaves, and clothes dryer while you are off-grid.
If you throw a hotmail.com at the end of my handle, you can drop me an email and I'll buzz you back with the publication info on that book. I have it at home in a bookcase with all my college stuff.