Solar panels, are they worth it?

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anonforthis
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Solar panels, are they worth it?

Post by anonforthis »

We live in Texas DFW. It gets really hot from June to Oct and our electric bills are way high during these months. Our home is 3500 square feet 5 bedrooms 4 baths, 2 levels home. It takes a lot to cool or heat up the 2nd floor. We only have electricity no gas in our home. We live on 20 acres rural area therefore the service charge to get the electricity to us alone is $30 a month. Last year, our bills were about $500 during the summer. Now our kids getting older and getting their own room, our bills may be higher than just us. We would like to invest some money in solar panels. What do you guys think? Thank you.
Novine
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Re: Solar panels, are they worth it?

Post by Novine »

Can you provide some numbers in kWhs on usage during the summers months? That would help with running the numbers on how much of an impact solar could have on your bill.
Visceral
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Re: Solar panels, are they worth it?

Post by Visceral »

I had an extremely high bill last summer as well, on a similarly sized home. The technician came out and said the refrigerant was very low and the unit was staying on because it could never cool the top floor down enough. They added refrigerant, and the bill dropped the next month to normal levels. Have you had yours checked?
Quickfoot
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Re: Solar panels, are they worth it?

Post by Quickfoot »

Both the kwh and the rate you are charged per kwh. Most utilities charge more in the summer and they also increase your rate once you consume a certain amount of power.

Solar Panels have reached a point where they are worth it if you are going to stay in the house 10+ years, if your power usage is very high it probably wont take as long as normal to get your money back. What you would be looking for more than likely is a grid tie solar system, these systems don't store power in batteries instead if your house doesn't use the power it goes onto the grid for other people to use and you get a credit on your bill.

Grid tie systems require permits from your utility company so you'll want to make sure to check with them if you decide to proceed.
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anonforthis
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Re: Solar panels, are they worth it?

Post by anonforthis »

Novine wrote:Can you provide some numbers in kWhs on usage during the summers months? That would help with running the numbers on how much of an impact solar could have on your bill.
It's about 6100 to 6500 kWh during the summer months.
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anonforthis
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Re: Solar panels, are they worth it?

Post by anonforthis »

Quickfoot wrote:Both the kwh and the rate you are charged per kwh. Most utilities charge more in the summer and they also increase your rate once you consume a certain amount of power.

Solar Panels have reached a point where they are worth it if you are going to stay in the house 10+ years, if your power usage is very high it probably wont take as long as normal to get your money back. What you would be looking for more than likely is a grid tie solar system, these systems don't store power in batteries instead if your house doesn't use the power it goes onto the grid for other people to use and you get a credit on your bill.

Grid tie systems require permits from your utility company so you'll want to make sure to check with them if you decide to proceed.

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Sbashore
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Re: Solar panels, are they worth it?

Post by Sbashore »

I live in the Phoenix area and own two homes in this area, one with solar and one without. When I put solar in on my first home in 2007, with the subsidies and tax breaks, my break even point was about 10 years with about 50% of the cost covered by the subsidies and tax breaks. When I built a second home in 2010 I did an analysis and it turned out to not be cost effective. The tax breaks and subsidies have declined since I originally installed solar. Another thought, solar panels become less efficient with heat. Their output is a function of sun angle and ambient temperature. Our peak months here are May and October because of this combination. That said, they crank out electricity in whatever quantity when the sun is up. My opinion is that they are not worth it at this point in time, unless subsidies and tax breaks in your area are sufficient to justify the investment.
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Re: Solar panels, are they worth it?

Post by Quickfoot »

Solar is very cheap these days, it's the difference between granite in the kitchen and not having granite in the kitchen. With 0 subsidies / tax breaks we could 100% power our 2500 sqft house for about 12K and would have 100% of our money back in savings in 11.1 years and we have VERY cheap power. Average life of solar panels where they are generating 80-90% of original power is 20+ years so we'd essentially get 8-10 years of free power if we stayed for 20 years.
It's about 6100 to 6500 kWh during the summer months.
That's a massive amount of power usage. What are you using in the winter?

If you are really using 6500 kWh you are going to want to look at ways to decrease your energy usage (better insulation, higher efficiency a/c, new windows, etc) BEFORE you get solar panels. Also look at smart thermostats that will increase the temperature while you are not in the house, they can save energy. You'll also want to get your existing A/C checked out immediately to make sure you don't have leaky ducts and your A/C is charged and operating normally. Also make sure you don't have the temperature set too low. You might also get a Kill A Watt meter and see if you can identify any appliances or electronics in your house using excessive power.

You might also want to look at evaporitive cooling if your humidity is low enough, you can get whole house evaporitive coolers that are many times more energy efficient than regular a/c.

A 6000 watt grid tie solar kit that generates 850 kwh per month is about 10K NOT including installation so it's not going to be cost effective until you make your house more energy efficient or fix /replace appliances. 850 kwh / month would replace about 80% of the power we use for our 2500 sqft house in Idaho which gets around 104 in the summer and down to 0 in the winter.

Even a 20,000 watt solar array only generates about 2716 kwh and that's at a cost of 30K without installation, even using 250 watt panels it's 80 solar panels.
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anonforthis
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Re: Solar panels, are they worth it?

Post by anonforthis »

Quickfoot wrote:Both the kwh and the rate you are charged per kwh. Most utilities charge more in the summer and they also increase your rate once you consume a certain amount of power.

Solar Panels have reached a point where they are worth it if you are going to stay in the house 10+ years, if your power usage is very high it probably wont take as long as normal to get your money back. What you would be looking for more than likely is a grid tie solar system, these systems don't store power in batteries instead if your house doesn't use the power it goes onto the grid for other people to use and you get a credit on your bill.

Grid tie systems require permits from your utility company so you'll want to make sure to check with them if you decide to proceed.
We will look into grid tie system. Thank you
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Re: Solar panels, are they worth it?

Post by Sidney »

How well sealed and insulated is the house and HVAC system (ducts)? Sometimes investing in this is a pretty good payback. Often rebates through utilities and/or state govt.
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anonforthis
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Re: Solar panels, are they worth it?

Post by anonforthis »

Quickfoot wrote:Solar is very cheap these days, it's the difference between granite in the kitchen and not having granite in the kitchen. With 0 subsidies / tax breaks we could 100% power our 2500 sqft house for about 12K and would have 100% of our money back in savings in 11.1 years and we have VERY cheap power. Average life of solar panels where they are generating 80-90% of original power is 20+ years so we'd essentially get 8-10 years of free power if we stayed for 20 years.
It's about 6100 to 6500 kWh during the summer months.
That's a massive amount of power usage. What are you using in the winter?

If you are really using 6500 kWh you are going to want to look at ways to decrease your energy usage (better insulation, higher efficiency a/c, new windows, etc) BEFORE you get solar panels. Also look at smart thermostats that will increase the temperature while you are not in the house, they can save energy. You'll also want to get your existing A/C checked out immediately to make sure you don't have leaky ducts and your A/C is charged and operating normally. Also make sure you don't have the temperature set too low. You might also get a Kill A Watt meter and see if you can identify any appliances or electronics in your house using excessive power.

You might also want to look at evaporitive cooling if your humidity is low enough, you can get whole house evaporitive coolers that are many times more energy efficient than regular a/c.

A 6000 watt grid tie solar kit that generates 850 kwh per month is about 10K NOT including installation so it's not going to be cost effective until you make your house more energy efficient or fix /replace appliances. 850 kwh / month would replace about 80% of the power we use for our 2500 sqft house in Idaho which gets around 104 in the summer and down to 0 in the winter.

Even a 20,000 watt solar array only generates about 2716 kwh and that's at a cost of 30K without installation, even using 250 watt panels it's 80 solar panels.

We use about 3000 to 3500 kwh in the winter. We did a major remodel this year so the electric bills will be less than last year. We still want to invest in some kind of solar power though. The grid tie systems sound really good. My husband and I will look into it.
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Re: Solar panels, are they worth it?

Post by herbie »

Sidney wrote:How well sealed and insulated is the house and HVAC system (ducts)? Sometimes investing in this is a pretty good payback. Often rebates through utilities and/or state govt.
I agree to start here. We have the ability to get energy audits in our state that evaluate these factors. Adding insulation to an attic can make a BIG difference for a small investment!
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Re: Solar panels, are they worth it?

Post by vtMaps »

'Quickfoot' had it right...
First thing to do is call the power company. You can't do grid tie unless you do it their way.

It will be cheaper to conserve a watt than to generate a watt. Once you've done major conservation, your electric bills may go down enough that you may not feel the need for solar.

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Re: Solar panels, are they worth it?

Post by mw1739 »

anonforthis wrote:It's about 6100 to 6500 kWh during the summer months.
As another poster said, that is a massive amount of energy for a 3500 sq. ft house. Although I'm in the Midwest, my home is nearly twice as big and the most energy we've ever used is 2600 kWh. I would look at upgrading HVAC systems before I dropped money on solar.
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Re: Solar panels, are they worth it?

Post by ThatGuy »

anonforthis wrote:It's about 6100 to 6500 kWh during the summer months.
Holy crap, what are you doing!?! I just checked my May bill, and I used 270 kWh for the month. I echo the suggestion of a Kill-O-Watt.

http://www.amazon.com/P3-P4482-Kill-Wat ... B007FGUIHC
Quickfoot wrote:A 6000 watt grid tie solar kit that generates 850 kwh per month is about 10K NOT including installation so it's not going to be cost effective until you make your house more energy efficient or fix /replace appliances. 850 kwh / month would replace about 80% of the power we use for our 2500 sqft house in Idaho which gets around 104 in the summer and down to 0 in the winter.

Even a 20,000 watt solar array only generates about 2716 kwh and that's at a cost of 30K without installation, even using 250 watt panels it's 80 solar panels.
Just to clarify, this depends also on how many hours of sunlight you get in your location, as well as some other efficiencies. Texas will have a higher average than Minnesota, for instance. If you don't want to lookup the actual numbers you can ballpark it with 6 hours/day at 72% efficient.

I like to do a reality check for grid tie systems with Mr Solar.
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Re: Solar panels, are they worth it?

Post by anonforthis »

Last month, we only used 800 kwh. We would like to invest about 20K in a good solar power system. We have space and land to put a good one in. My hushand and I will drive to Austin to attend their solar power meeting this year.
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Re: Solar panels, are they worth it?

Post by VGisforme »

So instead of quitting and moving to a tropical island now you'll start building a solar farm?

What's next week, join the circus? :)
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Re: Solar panels, are they worth it?

Post by anonforthis »

VGisforme wrote:So instead of quitting and moving to a tropical island now you'll start building a solar farm?

What's next week, join the circus? :)

Maybe. We have a lot of choices!

Like some here would say, there are many roads to Dublin.
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Re: Solar panels, are they worth it?

Post by BigFoot48 »

A while back I noticed a Costco a grid-tied solar panel system for $13,000, uninstalled and before credits. Since my neighbor suggested we have Solar City give us a presentation (he offered to split the $100 they would give him to host a presentation), I decided to look at it. I see it claims "The Grape Solar 5170Watt Grid-Tied PV Kit can generate between 310kWh and 723kWh of electricity per month." http://www.costco.com/5170-Watt-Grid-Ti ... 30267.html

So for $13,000+, say $16,000 with taxes and installed, I could possible save at $0.11kWh between $34 and $80 a month, or $408 to $960 a year - a 17 to 39 year payback period, before tax credits, rate increases, and ignoring the investment foregone. If tax credits were 50% it might be 8 to 20 years. I can see that being interesting to someone planning to be in a house a long time, but it doesn't do much for me at 65.

I do notice a fair number of solar systems going onto houses in our neighborhood, and that of my mother-in-law up in Sun City West.
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wjo
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Re: Solar panels, are they worth it?

Post by wjo »

OP - I was in the same situation a few years ago. All electric, sunny and hot.

I put in 5.8kW of solar panels and a solar hot water system. Payback was about 4%+ (not bad as that is tax free). I suspect it would be better return now as things have become cheaper.

Definitely explore a solar hot water system if you are all electric. The payback on that one is better than solar panels. They have tubes that are heated by the sun that then heats a reserve tank. The reserve tank then feeds the main hot water tank for the house - you are essentially feeding heated water so you don't have to heat it using power.

Use an experienced installer - check references.
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Re: Solar panels, are they worth it?

Post by Sbashore »

BigFoot48 wrote:A while back I noticed a Costco a grid-tied solar panel system for $13,000, uninstalled and before credits. Since my neighbor suggested we have Solar City give us a presentation (he offered to split the $100 they would give him), I decided to look at it. I see it claims "The Grape Solar 5170Watt Grid-Tied PV Kit can generate between 310kWh and 723kWh of electricity per month." http://www.costco.com/5170-Watt-Grid-Ti ... 30267.html

So for $13,000+, say $16,000 with taxes and installed, I could possible save a $0.11kWh between $34 and $80 a month, or $408 to $960 a year - a 17 to 39 year payback period, before tax credits, rate increases, and ignoring the investment foregone. If tax credits were 50% it might be 8 to 20 years. I can see that being interesting to someone planning to be in a house a long time, but it doesn't do much for me at 65.

I do notice a fair number of solar systems going onto houses in our neighborhood, and that of my mother-in-law up in Sun City West.
Sounds like your analysis is a lot like mine was, for this area. When payback gets out beyond 10 years, I lose interest. :D
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Re: Solar panels, are they worth it?

Post by Retread »

Just want to echo the thoughts of others that this is an enormous amount of power consumption. We live in South Florida year round in a 4,250 square foot house with two units running and our high consumption last summer was 2,750 kwh.
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Re: Solar panels, are they worth it?

Post by kenyan »

anonforthis wrote:
Novine wrote:Can you provide some numbers in kWhs on usage during the summers months? That would help with running the numbers on how much of an impact solar could have on your bill.
It's about 6100 to 6500 kWh during the summer months.
Wow, those are some low rates you pay on electricity. That would be a $2000 bill where I live.
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Re: Solar panels, are they worth it?

Post by perl »

You might look into solar leases. I don't have personal experience with them but friends have had solar panels installed with no upfront cost, and the lease payment is less than their savings on their electric bill.
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Re: Solar panels, are they worth it?

Post by jebmke »

Retread wrote:Just want to echo the thoughts of others that this is an enormous amount of power consumption. We live in South Florida year round in a 4,250 square foot house with two units running and our high consumption last summer was 2,750 kwh.
Bruce
1,500 - 1,600 kwh for 2600 sq ft in mid Atlantic for hot summer month. We're all electric so that includes AC, well, HW, pool pump etc. Did a lot of insulation three years ago. Last year remodeled sunroom with low-E glass. I'd guess we cut 25% from our usage for peak summer and winter months.
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Re: Solar panels, are they worth it?

Post by anonforthis »

Retread wrote:Just want to echo the thoughts of others that this is an enormous amount of power consumption. We live in South Florida year round in a 4,250 square foot house with two units running and our high consumption last summer was 2,750 kwh.
Bruce
I went over board on the AC cause I just had baby and I was home all day. We will cut back on it so this year will be a lot less. We have 3 units.
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Re: Solar panels, are they worth it?

Post by jebmke »

Still sounds like a lot of kwh for the space. I'd echo other suggestions to get an energy audit. Usually they are free. We found that there were a few places that were huge heat loss/heat gain (summer) and we were able to do a lot just by closing up these losses. It also made the house more comfortable and even temperature.
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Re: Solar panels, are they worth it?

Post by Alskar »

anonforthis wrote:We live in Texas DFW. It gets really hot from June to Oct and our electric bills are way high during these months. Our home is 3500 square feet 5 bedrooms 4 baths, 2 levels home. It takes a lot to cool or heat up the 2nd floor. We only have electricity no gas in our home. We live on 20 acres rural area therefore the service charge to get the electricity to us alone is $30 a month. Last year, our bills were about $500 during the summer. Now our kids getting older and getting their own room, our bills may be higher than just us. We would like to invest some money in solar panels. What do you guys think? Thank you.
I'm an electrical engineer. At my last job I designed PV solar power optimizers and micro-inverters. As such, I am pretty familiar with the tradeoffs. Investing in solar panels may or may not be worth it depending on a host of issues that include:

1. Your time horizon
2. How many square feet of roof space is appropriately oriented to capture the sun
3. The cost of electricity in your area.
4. Whether you have a so-called "feed in tariff" in your area.
5. Your eligibility for any subsidies.

Without knowing the specifics, it is really impossible to make a quantitative decision. However, here are some things to consider:

1. PV solar panels get MUCH less efficient when they're hot. So they're not going to produce as much electricity as you think they will during the months when you want to run the AC.
2. Dust is a real issue. If you live in a dusty area, either install one of the automatic washing systems, or plan to wash the panels off once a week to maintain efficiency.
3. This is controversial, but IMHO I would not install micro-inverters, especially in a hot climate. They will not last as long or be as efficient as the manufacturer claims. I would install a conventional central inverter. I personally would choose an inverter from Eltek Valere as I was impressed with their inverters.
4. Chinese-made solar panels are less expensive per kilowatt, but tend to degrade faster over time because of the way the silicon is processed. I personally would spend the extra money and get Solar World panels.
5. There are hundreds of poorly qualified solar installers out there. I see new, shabby installations every time I walk around my neighborhood. I live very near the 45th parallel. That means solar panels should be at 45 deg from the horizontal. I see panels at all kinds of crazy angles that make no sense. Nuts! If you're going to invest in PV solar, hire an installer that will do a real site survey and understand the notion of latitude.

If you're looking for a quick financial payback, I don't think PV solar is worth it. If you're interested in lowering your carbon footprint, then PV solar is probably a reasonable choice.
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Re: Solar panels, are they worth it?

Post by heavywhether »

Improving the energy efficiency of the “building envelope” goes a long way. We spray foamed the roof (not the attic floor) of our house, and while we were replacing windows, added a one-inch layer of foil-faced rigid foam board on the outside face of the walls since we had to replace the siding anyways. This was about five years ago. Recently while doing some energy analysis, I added up the home heating oil we had consumed for heat and hot water for the ten years prior to the work I described, and then for five years following the work. The volume of oil consumed dropped to 60% per year, based on actual oil purchase data from 10 and 5 years respectively. We had also replaced our old/ancient central AC system with a new one. The new system runs through the cooling season, whereas the old (ancient) one ran only when it was really hot. With the efficiency of the new system, we are more comfortable and our KWh usage has not gone up any.

A properly sized and designed HVAC system helps get the most from the energy used. Central systems are generally more comfortable (consistent) and efficient than window units. If the three units you mention are window or wall units, replacement with a central air-conditioning system is worth considering, although retrofitting into an existing house can have its challenges.

With long paybacks, the analysis gets very sensitive to a slight variation in a variable. Even ten years seems long for a payback period, and I too lose interest.
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Re: Solar panels, are they worth it?

Post by madbrain »

anonforthis wrote:
Novine wrote:Can you provide some numbers in kWhs on usage during the summers months? That would help with running the numbers on how much of an impact solar could have on your bill.
It's about 6100 to 6500 kWh during the summer months.
That's crazy. Here in San Jose, the monthly bill would be over $2,000 for this amount of energy.
You would need about 120 typical 240W solar panels to cover your entire electricity usage in summer months. Ie. about a 28.8 kW solar system.
At a typical $4/watt for an installed system after incentives, that would run you about $115,000 . It could probably be done for less than $4/watt, but probably not much under $3/watt.

I have a 4700 sq ft house, with one 100% electric car that's charged only at home, two central AC, a hot tub, a sauna, 7 computers, home theater, 3 TVs, 240 lightbulbs, 1 huge 48" fridge, very large freezer in the garage, and 3 beverage/wine coolers, and our usage, assuming no solar system, has never topped 1800 kWh/month. On average it's about 46 kWh per day which is 1400 kWh per month. And we do take energy efficiency seriously and still think it's too much.
I know there is a lot of "vampire load" in the house, which means we could in theory cut usage further, but replacing all those devices that draw the vampire loads would be too expensive or not possible - like my network laser printer that draws 40W idle, each HVAC controller that draws 40W idle, some major kitchen appliances like my oven and cooktop that inexplicably draw about 30-40W idle as well, the DVR which draws 60W 24/7. This all adds up to 800W of vampire load which is 19 kWh per day or 570 kWh per month, or 40% of our monthly electric usage !
Last year our 40 panel , 9.6 kWh solar system covered 99% of our annual electric bill, which would have been $5,200 without a solar system in place.

You need to figure out where all that energy is going long before you put in solar. Do you have a pool ? Hot tub ? Do you grow pot ?
Another poster suggested using a Kill-o-watt. This is a good idea, but IMO it probably won't find the major sources of energy usage when you are dealing with such a huge number. That's because a Kill-o-watt is a plug-in device. It won't measure the usage from major hardwired 220V circuit, like an electric car charger, pool heater, hot tubheater, sauna heater, clothes dryer, electric oven, electric cooktop, etc.

Start by looking at your electric meter and looking at the instant usage in kW, hopefully displayed. Then turn some breakers one at a time and take note of how much the instant usage goes down. This may not work for some devices as some devices like AC and pool heaters will turn on/off periodically based on the air/water temperature. If there is no instant display on your meter, or for those devices that aren't on all the time, then just look at the meter from one day to the next. Leave the pool heater off for one day, AC off for one day, etc. And then see how much your daily usage goes down. It may take a while to figure out, but it's really important to get the big picture. For your size house, you should be able to bring your usage below 2000 kWh/month in the summer. Then when you have done that, you can think about putting in solar.
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Re: Solar panels, are they worth it?

Post by LadyGeek »

This thread is now in the Personal Consumer Issues forum (solar panels).
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Re: Solar panels, are they worth it?

Post by Wildebeest »

anonforthis wrote:This is our forever home unless we decide to move back to my country.
We did get solar panels considering we had to live here for 15 years to get ROI. That is commitment or delusion.

Does your SO like your country? I have a hard time imaging any place like Texas other then Oklahoma or the out back in Australia.

Am I close?
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Re: Solar panels, are they worth it?

Post by Quickfoot »

I have a hard time imaging any place like Texas other then Oklahoma or the out back in Australia.

Am I close?
Not quite, the DFW metroplex has 6.5 million people which is 1.65 times the population of the state of Oklahoma, 2.29 times the population of the state of Nevada and equal to the population of the state of Arizona. Its population is greater than the countries of Denmark, Finland, Slovakia, Norway, Georgia, Ireland, and Croatia to name a few.
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Re: Solar panels, are they worth it?

Post by Mike83 »

Some things you should do BEFORE solar electric:
1] you are in an area with many pools: a variable speed swimming pool pump could reduce your electric bill $35 per month
2] you are in a relatively warm weather climate: a heat exchange hot water heater (GE Geospring) will save you another $35 per month and produce the equivalent savings of solar hot water at 20% of the installed cost
3] residential lighting represents 17% of your electric load, invest a few hundred $ in led lighting (I recommend Philips product line at 2700 kelvin, dimmable and sensor friendly) and reduce your lighting load from 17% to 3% of consumption. In Texas, lights are also a net heat generator that air-conditioning has to remove, so you save twice on this purchase. If kids are coming, install California type occupancy sensors set in 'vacancy' mode. Turn the light on with a switch, but off if nobody stays in the room (reduces dad blood pressure by 5 points!).
4] the sun is strong in Texas. Install selective window films (not tints) that allow light but block SOLAR heat. Your really have only one choice on the market if you don't want to darken the windows: 3M products, professionally installed. Just do sunny windows, perhaps west facing. Perhaps $800.
5] you are in a heavy a/c usage area; IF your a/c is in an attic above the insulation, consider removing the insulation and applying spray thermofoam to the underside of the roof. This is expensive, over $10000, but hey you are considering solar electric. This will reduce your ac cost.
6] now have an a/c contractor or preferably a paid engineer do a 'manual J' load calculation on your house. If you have done 1-5 you will now be able to downsize your a//c tonnage and reduce your electric bill perhaps $400/yr if you also upgrade to amore efficient unit (especially if your current unit is 15 years old.
7] Only at this point should you consider solar electric roof panels, and if you do, the best time to install is when you have just replaced your roof with a finish that will last 30 years. Solar power is very expensive and you want to reduce power consumption by any other method prior to selecting and sizing a system. Unfortunately, if you have a new roof, the panel installation immediately put quite few penetrations in it.
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interplanetjanet
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Re: Solar panels, are they worth it?

Post by interplanetjanet »

Seconding (thirding) other posters - find out where the power is going and do what efficiency improvements you can first. Sealing air leaks can make a huge difference in older houses, consider getting an energy audit performed including a blower door test. If a roof replacement is on the horizon, consider more thermally efficient roofs (white painted metal is especially popular in some areas including parts of Australia, where they know about heat). Consider an attic fan or fans if you do not have one already.

Your cost for electricity is relatively low and so PV solar will have a longer payback than in many other areas. You are probably right to consider freestanding solar as opposed to roof-mounted given that you have plenty of land. The panels can be placed at optimal angles to catch the most light and future roof work will not require panel removal, and the panels themselves will have better air circulation and should remain cooler - greater efficiency.

I thought my power consumption was high at around 1200kw-h/mo, and I pay not that much less per month than you do. It gets past 110F here sometimes in the summer.
Valuethinker
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Re: Solar panels, are they worth it?

Post by Valuethinker »

Mike83 wrote:Some things you should do BEFORE solar electric:
1] you are in an area with many pools: a variable speed swimming pool pump could reduce your electric bill $35 per month
2] you are in a relatively warm weather climate: a heat exchange hot water heater (GE Geospring) will save you another $35 per month and produce the equivalent savings of solar hot water at 20% of the installed cost
3] residential lighting represents 17% of your electric load, invest a few hundred $ in led lighting (I recommend Philips product line at 2700 kelvin, dimmable and sensor friendly) and reduce your lighting load from 17% to 3% of consumption. In Texas, lights are also a net heat generator that air-conditioning has to remove, so you save twice on this purchase. If kids are coming, install California type occupancy sensors set in 'vacancy' mode. Turn the light on with a switch, but off if nobody stays in the room (reduces dad blood pressure by 5 points!).
4] the sun is strong in Texas. Install selective window films (not tints) that allow light but block SOLAR heat. Your really have only one choice on the market if you don't want to darken the windows: 3M products, professionally installed. Just do sunny windows, perhaps west facing. Perhaps $800.
5] you are in a heavy a/c usage area; IF your a/c is in an attic above the insulation, consider removing the insulation and applying spray thermofoam to the underside of the roof. This is expensive, over $10000, but hey you are considering solar electric. This will reduce your ac cost.
6] now have an a/c contractor or preferably a paid engineer do a 'manual J' load calculation on your house. If you have done 1-5 you will now be able to downsize your a//c tonnage and reduce your electric bill perhaps $400/yr if you also upgrade to amore efficient unit (especially if your current unit is 15 years old.
7] Only at this point should you consider solar electric roof panels, and if you do, the best time to install is when you have just replaced your roof with a finish that will last 30 years. Solar power is very expensive and you want to reduce power consumption by any other method prior to selecting and sizing a system. Unfortunately, if you have a new roof, the panel installation immediately put quite few penetrations in it.
+1 all very helpful

Creating new energy (solar) is the last line in these things vs. conservation. Particularly basic things like LED lights.

If there is an old fridge (pre 1992) around then it could be burning 1200-2000 kwhr pa (plus as you point out heating the house up) vs 600 kwhr for a new model. Along with replacing lights with LED bulbs (and I second re Philips quality and the 'warm' color of the 2700K) it's a really easy thing to do with a surprisingly quick payback. Old computer equipment can also be a real power hog (the industry has really cleaned up its act, and President Bush signed a law and the US is ahead of us in Europe on this).

If you have a lot of kids say then heating and drying can take up a lot of energy-- a top loading washing machine can burn 3-4 kwhr per load, and drying as much again.

If sounds like the OP has an AC problem. In which case I doubt lighting is 17% of the bill. But it's still low hanging fruit.
HIinvestor
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Re: Solar panels, are they worth it?

Post by HIinvestor »

We have a ridge roof vent that has helped passively cool our home. Solar roof fans and good insulation in the attic and roof really help keep the house a more comfortable temperature. My H and S installed Mylar aluminum bubble wrap type insulation in our attic and it has made a HUGE difference in moderating the temperature in our home.

We have a 1250 sq ft home and have been averaging between 111 to 395 KWH/month. We do have a solar water heater and run two computers nearly 24/7. We got back 65% in fed and HI rebates for our PhotoVoltaic installation. Because our energy codys are highest in the US at $.37/kWh it seemed a good investment to us. They told us it would only cost about $500 to remove and reinstall the PV panels when we need to reroof, as we only have 9 panels.
goblue100
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Re: Solar panels, are they worth it?

Post by goblue100 »

anonforthis wrote:We live in Texas DFW. It gets really hot from June to Oct and our electric bills are way high during these months. Our home is 3500 square feet 5 bedrooms 4 baths, 2 levels home. It takes a lot to cool or heat up the 2nd floor. We only have electricity no gas in our home. We live on 20 acres rural area therefore the service charge to get the electricity to us alone is $30 a month. Last year, our bills were about $500 during the summer. Now our kids getting older and getting their own room, our bills may be higher than just us. We would like to invest some money in solar panels. What do you guys think? Thank you.
I also live in DFW and would echo everyone that using 6500 kwh in a month sounds like a huge amount. I also have 2 story 2800 sf house, and I use at most 3500 kwh in the summer, and I have a pool with pump motors. You mentioned heating or cooling the second story as a problem, do you have an upstairs and downstairs AC / furnace? Two units are often way more efficient than one big one. I agree with everyone that fixing the consumption side of the issue would be a better use of dollars then trying to produce electricity. If you really want to generate, you should at least check out wind turbines as well, since you are rural and have land to put them on. I am no expert but you might get more for your dollar with wind.

Also, my electric bill breaks down into usage and delivery. It is not because you are rural that it cost you $30, Texas breaks the bill into usage which goes to your electricity provider, and delivery, which goes to Oncor.
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Userdc
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Re: Solar panels, are they worth it?

Post by Userdc »

Maybe OP could clarify, but when I read that they use 6100 to 6500 for the summer months, that means they are using approx 2000 per month in the summer. Which seems a lot more reasonable and fits in with some of the other facts.
gerrym51
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Re: Solar panels, are they worth it?

Post by gerrym51 »

If you plan on staying where you are then -maybe.
Easy Rhino
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Re: Solar panels, are they worth it?

Post by Easy Rhino »

yeah 6000kw in one month seems off. Maybe you need your own utility plant :)

So.. what everyone else has said. Look up through your utility to see if they have any sort of home energy audits. Maybe you can get one free or for only a few hundred bucks. Our audit was very educational it even presented the estimated efficiency gains from different home improvements.

Your house sounds... complicated, so there may be unforseen opportunities.

We just spent almost $15k on home energy improvements on our house. our electric consumption is much lower, only 4-500 kwh per month in the winter (smaller house and most appliances are gas). The payback period is... really long, well over 10 years, but many of the changes were comfort items, as the house was so darn drafty before.

Pool? variable speed pump will save lots of electricity, and solar water heater is more likely to be cost effective with pools as well.

3 a/c units might be too many. You might get more efficiency from only two. just speculating here.

look up your electricity bill to see how tiered your rates are. here there are four tiers, and the top 2 are very expensive. Some folks will size their solar install just to get into the lower tiers. They're not trying for zero footprint or anything.
Professor Emeritus
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Re: Solar panels, are they worth it?

Post by Professor Emeritus »

Quickfoot wrote:
I have a hard time imaging any place like Texas other then Oklahoma or the out back in Australia.

Am I close?
Not quite, the DFW metroplex has 6.5 million people which is 1.65 times the population of the state of Oklahoma, 2.29 times the population of the state of Nevada and equal to the population of the state of Arizona. Its population is greater than the countries of Denmark, Finland, Slovakia, Norway, Georgia, Ireland, and Croatia to name a few.
:happy but the number of tourists who actually visit the metroplex for it's attractions ranks with Des Moines :happy

BIL was a judge in Tarrant county. We know it well
Valuethinker
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Re: Solar panels, are they worth it?

Post by Valuethinker »

Easy Rhino wrote:yeah 6000kw in one month seems off. Maybe you need your own utility plant :)

So.. what everyone else has said. Look up through your utility to see if they have any sort of home energy audits. Maybe you can get one free or for only a few hundred bucks. Our audit was very educational it even presented the estimated efficiency gains from different home improvements.

Your house sounds... complicated, so there may be unforseen opportunities.

We just spent almost $15k on home energy improvements on our house. our electric consumption is much lower, only 4-500 kwh per month in the winter (smaller house and most appliances are gas). The payback period is... really long, well over 10 years, but many of the changes were comfort items, as the house was so darn drafty before.

Pool? variable speed pump will save lots of electricity, and solar water heater is more likely to be cost effective with pools as well.

3 a/c units might be too many. You might get more efficiency from only two. just speculating here.

look up your electricity bill to see how tiered your rates are. here there are four tiers, and the top 2 are very expensive. Some folks will size their solar install just to get into the lower tiers. They're not trying for zero footprint or anything.
The problem in Texas is presumably humidity?

And so variable speed (or dual speed) air con makes a significant difference. Because the AC is likely running too much -- cycling from too cold to too hot and back. It's the humidity that creates the discomfort rather than say the desert heat of California or Arizona. Granted new HVAC is a big cost, but at least cleaning and sealing the ducts, plus getting the suggested utility audit-- utilities are usually incentivized by the regulator to make energy efficiency investments.
Valuethinker
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Re: Solar panels, are they worth it?

Post by Valuethinker »

Professor Emeritus wrote:
Quickfoot wrote:
I have a hard time imaging any place like Texas other then Oklahoma or the out back in Australia.

Am I close?
Not quite, the DFW metroplex has 6.5 million people which is 1.65 times the population of the state of Oklahoma, 2.29 times the population of the state of Nevada and equal to the population of the state of Arizona. Its population is greater than the countries of Denmark, Finland, Slovakia, Norway, Georgia, Ireland, and Croatia to name a few.
:happy but the number of tourists who actually visit the metroplex for it's attractions ranks with Des Moines :happy

BIL was a judge in Tarrant county. We know it well
The ex-urban supersprawl aka 'there's no there there'. DFW and Atlanta are 'cities of tomorrow' and that form has its problems (see also Shenzen in China, the richest region, across the border from Hong Kong, but all spread out).

There are some excellent art museums I believe? I know more about Houston, and Houston has a *lot* of culture (art, music, theatre) which those of us from older (snobbier?) cities consistently under rate.
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BigFoot48
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Re: Solar panels, are they worth it?

Post by BigFoot48 »

Article on the impact of leased solar panels on home sales:
Dorian Bishopp blames the solar panels on his roof for costing him almost 10 percent off the value of the home he sold in March.
http://www.bloomberg.com/news/2014-06-2 ... -sell.html
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aerofreaky11
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Re: Solar panels, are they worth it?

Post by aerofreaky11 »

I have to agree that insulation is the first step. You're describing issues on the 2nd floor. Get as much insulation as you can in there and research powered thermostatically controlled fans etc... I have first hand experience of cutting energy consumption by 1/3 from better insulation. R 19 was a joke. It didn't cost a lot either and there were tax incentives.
freddie
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Re: Solar panels, are they worth it?

Post by freddie »

BigFoot48 wrote:Article on the impact of leased solar panels on home sales:
Dorian Bishopp blames the solar panels on his roof for costing him almost 10 percent off the value of the home he sold in March.
http://www.bloomberg.com/news/2014-06-2 ... -sell.html

I have no idea if the panels cost him 10% (homeowners are notorious for inflated views of the worth of their property) but yeah I wouldn't buy a house with a solar lease either unless I had to. I would much rather have a recent system with a company I choose so I would need a discount to consider it.
Jack FFR1846
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Re: Solar panels, are they worth it?

Post by Jack FFR1846 »

Any state incentives in Texas?

In Massachusetts, you can't walk into a Lowes without a solar company booth showing you free installation, no payment solar. Our state has great incentives and fronts the money for what it expects the solar panels will put out before they even get hooked up. We have far fewer solar hours than Texas does. I can think of at least 20 new huge solar farms (10 acres or more each) within 20 miles of me.
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Lafder
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Re: Solar panels, are they worth it?

Post by Lafder »

I am not the OP but it is the same question with specific numbers.

I will start a new post.

lafder
Last edited by Lafder on Sun Jul 13, 2014 9:07 pm, edited 1 time in total.
Novine
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Re: Solar panels, are they worth it?

Post by Novine »

Someone who had only one offer on their house in 5 months has bigger problems than leased solar panels on their roof.
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