Sorry, no that’s not true. Greater degrees of tilt will certainly help when the weather warms up but they are simply not self cleaning.
As far as optimal angle for sunlight, that varies depending on latitude. There is no single optimal angle.
Is this a matter of semantics?
Are you saying NO snow sloughs or melts off regardless of angle, or are you saying there’s simply not ENOUGH of that?
I’m saying if you live in a snow state and want electricity then you will have to broom it off when it snows. The other option is to tilt them down ahead of time.
I can’t agree with this. I see plenty mounted on roofs here. There’s no way people are climbing up on the roof after every snowfall.
In Bavaria (with lots of sunshine and about 10% of solar panels on roofs), people usually don’t get on the roof in winter to clear the panels. And while the big farms for investment funds have a maintenance company under contract to clear them once or twice a year, even that is more for pollen dust, smoke particles and fall leaves than snow. The model is that if you calculate all snow covered days as equalling 2 months, the remaining 10 months of revenue more than make up for that.
That’s because solar is not for complete independence for houses in the far sticks, but rather, for one-family houses in the suburbs connected to the grid. So when the sun shines during the 10 months, the family uses what they need, and the rest is fed into the grid; when in winter the panels are covered, the family takes power from the grid.
If you live out in the boondocks and want to be indepent instead of paying for several hundred miles of power cable, then you need to combine solar with some kind of storage. A small version of water tank falling one meter and driving a dynamo, for example (pumped back up during the day/summer). Or you do hyrdolisis and store the hydrogen. Or you live far more southern in an area where snow only falls once every five years, and consider it worth it to clean the panels then. (And you space your electrical needs so that you use most of your power during the day - a question of planning and getting used to it.)
If you actually are living out in the sticks, you probably have enough space around that you can pick a spot that’s easier to access for cleaning than your roof - the above-mentioned one-family homes in the burbs put the panels on the roof because they have little space elsewhere.
in message 5 i stated
i wrote message 5 intending to indicate there are multiple angles with the phrase ‘… much of the areas …’. i suppose i could have pluralized angles though for any individual fixed collector the angle is singular and it seemed to read funny. i’m sorry that you were mislead by my phrasing.
the collectors in my area, which has snow, seem to self clean just fine.
Don’t know what to tell you. I’ve had cars with all kinds of window angles and snow always sticks to them. My utility company has a solar array facility andwhen it snows it sticks. Looking back on the date in the article there was 3 inches of snow over 2 days which is hardly a heavy snowfall.
If I had money pouring out my ass I would have a solar array big enough to power my house because I like the idea of being energy independent. But I’m not rich so it’s not happening. I may build an electric car to play with if the opportunity arises but that would be for the fun of having a 2nd or third car for short trips.
There are lots of people who have spent money on solar panels that will never pay back the cost on installation or the amount of energy it takes to create and install solar panels. Heck, my pbs station was promoting solar panels to charge you phone and calling them green. There is no way using solar panels for a couple of hours a day will ever pay back the energy used to make them. Energy and or cost payback only comes after about 5 to 15 years of running the panels during all daylight hours.
Please don’t repeat this falsehood again.
The energy payback time is under 4 years: http://www.siemenssolar.com/Energy_paper_index.html
and here: http://www.nrel.gov/docs/fy04osti/35489.pdf
For thin-film panels it is under 2 years.
i’ve seen a recent article cutting those times in half.
That’s just for the energy used to create them. The current state of PV’s are not economically feasible.
What does this even mean?
Of course they are- although they can’t compete with fossil fuels on a purely cost basis.
There are loads of applications where PV is the logical choice.
Please, 5 to 10 is really not very far off from 4 years. Your cites don’t really back up their calculations and they seem to fail to include the cost of the mounting hardware, the DC to AC conversion electronics etc.
I keep looking into putting solar on my house and even in San Diego with good sun and high electricity costs it really does not make economic sense. I use about 450 KWh a month at my house. The electricity bill is $69.09a month.
Let’s break down the calculations:
Assume fixed panels and assume 6 hours a day of full on sun. The daylight is longer than six hours a day but most of that time is not full on sun. I am also assume 100% sunny days. 450 Kwh is about 15 KWh a day. Divide by 6 is a 2.5 W system. I have not seen a system of around than size installed for less than $20,000. $20K is 24 years of electric bills.
The cost is getting better but single family photovoltaic solar currently is a feel good thing vs a thought out decision to save money on electricity.
When lots of people have grid tied solar system the current system of selling daytime electric power to the grid at the same price as you buy night time power will go away and the calculation become less favorable. When I look at my bill it is broken down in to several categories. $35.59 is for delivery charges. This is basically the cost of the grid. $2.26 is some bond repayment thing. $4.06 is taxes. $27.18 is the cost of the electric generation.
Realistically in a system that accounts for costs only the $27.18 is being offset by my panels now that is 61 years to pay back the cost of the system. In my opinion that is not realistic.
It means PV’s are a flaming waste of money. That’s what it means.
Yes, the space station, that little do-hickey on the side of highways, the atoll that Amelia Airhart washed up on, Berkley California…
As you said, they can’t compete with fossil fuels. Wouldn’t it make more sense to invest in something like geo-thermal that has a realistic return on investment and can be purchased by the average consumer?
There are two very different aspects here that need to be looked at seperately:
- The energy required to manufacture PV panels vs. the energy they produce.
This depends on the type of panel and the manufacturer. But it is very short with new manufacturing processes. It’s also very hypocritical to apply this only to solar panels and not to all other kinds of energy production.
- The money required to buy and install the panels vs. the money saved or earned with the power the produce.
This will vary widely depending on what pay-back (fixed or not) your local power provider pays for the energy you feed into the grid; how high your local power costs are; if the govt. offers a special low-interest credit for this or other incentives.
Excuse me, but why would you “run” them only a couple of hours a day??? Bavaria has 8 hrs/ sunshine on ** average per year**, or 1600 to 1900 cumulated per year (and no, despite accusations in the other thread, the DWD is not a “green conspiracy”, it’s the national weather service and neutral observer.) Considering that Bavaria is at latitude North of 48 Deg. and New York is already at 40 Deg., in fact, most of the US is far more southern than continental Europe, you’d expect a lot more sunshine than “a couple of hours”.
Yes, and? Why wouldn’t you do that? Do you believe it costs energy to “run” them? It’s not like you have to go outside and do anything. They run automatically. All you have to do is to decide whether you use the energy yourself, or fed them into the general grid.
Only in the US, only with the current low energy prices, and only if you take the US attitude that investments need to repay in 5 years, because then you will sell your house again.
In Germany, the typical one-family house is bought when people start their job, and then they live there for the rest of their live. Looking at 20 years payback on investment is normal length. People don’t want to sell their houses every 5 years.
You’re comparing apples to oranges here. I don’t know which kind of geothermal you mean - there are two common methods - but it has more requirements than solar.
First, PV panels can be put up in the cities on office buildings or other big flat roofs. You can’t put geothermic or water power plants there, but you can use otherwise wasted space.
Second, one-family homes with access to the grid have two different needs: heating (= thermal) and power. Heating varies wildly with how good the house is insulated, what type of heating system (apparently, the standard in the US is electric, which is incredibly wasteful from an energy standpoint, unlike central heating with gas or oil), related to that the cost of fuel for the heating system.
Power depends on the price of the provider, which varies from region to region, and how much the family uses.
In Germany, heating is a bigger expense than power, although the big 4 monopoly has jacked up the prices recently again. But with a modern 3 l. house, heating needs can be lowered.
The two types of geothermal currently in use are:
Geothermal for heating of small-family homes. This requires however a big yard where you bury several dozens of meters of pipes. This doesn’t solve the power needs of the family at all, however, because it’s only using the temp. diff. in the earth to heat water/ fluid. So you still need a way to produce power.
Geo power plants through hot springs (basically, a steam turbine). This is even more limited to those regions that are vulcanically active, but not too much, just hot water, and yet still accessible enough to build a plant. And then, it’s a big power plant, not something for the average family home.
Yes, but to get to that point where we can sustain and control a fission reaction without spending more energy (on the magnetic containment, on the acceleration etc.) is a very long road, and it’s complelty unclear / unknown if it is feasible at all under Earth conditions.
Even if a fission plant could be developed in 20 or 50 years, this still doesn’t automatically mean free energy for everybody. Aside from the fact that you need at least four power plants, because the US has four different power cable systems (and obviously current political attitude is too short-sighted to spend money towards infrastructure repairs and updates, no matter how sensible for multiple reasons and urgently necessary that is) - what if each plant costs 1 000 billion dollars to build? Getting that money isn’t easy, esp. if compared to the costs of keeping the current coal and nuclear plants running.
The dream some people espouse, of having a small fission reactor in each home to be indepent and get rid of the power cables and big power plants, sounds like a Sci-Fi dream to me. I can see no realistic way, short of finding some unobtainium or a Zero Point Module, to make that happen.
If you want the most efficient small power plant for a normal household, the realistic alternative is what’s called colloquially the Volkswagen power plant - a car engine (because they are already mass-produced, thoroughly tested and stable, easy to repair and get replacements for, and run on a variety of gas, diesel, oil) that produces both power and heat to warm the house. Using the waste heat of the engine for heating is the most efficient use of energy compared to single-use, gets up to 70% efficiency.
One of the green power companies, Lichtblick, wants to put 5 000 of these in German homes over the next years. They connect to the main grid, and whenever power is needed, they are fired up remotly. When the family itself needs the power, they use it; when they don’t, they shut the engine off; when everybody else needs energy, the engine turns on.
The talk about only a few hours a day was in response to my radio station selling solar phone chargers as green. You don’t run your solar phone charger during all the daylight hours. The solar phone chargers are not green at all. They will not save energy.
Solar panels have a life expectancy of 20 to 25 years and they don’t pay for themselves in that time frame. That’s ignoring the fact that they will likely be obsolete before that time. And that also ignores the expense of storing the power from solar cells during off hours. It is a very expensive source of power at this time so money would be better spent reducing power consumption (IE geo-thermal).
I was referring to geo-thermal HVAC systems which actually pay for themselves. It’s all about allocating money efficiently. It’s the same argument for electric cars. They are not financially efficient NOW but they will be in the future.
You mean like this example - a small pad that allows you to charge your cell phone? Those are for a special reason: if you are anywhere outdoors, you might be without access to normal chargers for some time. Or your battery drains unexpectdly because it’s in a weak reception area. Using this small module you can charge your cell phone for a quick emergency call.
Most cell phones don’t take normal batteries, so if the Akku runs out, and there’s no outlet around, you would be screwed. Not this way. What’s wrong with that?