# Solar panels vs. Coal, a matter of perspective?

### Solar panels vs. Coal, a matter of perspective?

I just went through calculations which show that for where I live, the direction of my house, the pitch of my roof, etc... 6,750 Watts worth of solar panels and their ancillary equipment will yield an annual output of 7,300 KWH of electricity.

In my opinion, the easiest way to compare electricity directly to coal is via BTU's.

7,300 KWH x 3,412 BTU's/KWH = 24,970,000 BTU's

Why, that is just about exactly the number of BTU's in a single ton of coal (if burned at 100% efficiency). Allowing for the inherent inefficiencies of coal, lets say 1.5 tons are required for equivalence, to grant as much favor to the solar panes as is possible. Therefore I will state that 1.5 tons of coal = 7,300 KWH of electricity, useable BTU for useable BTU.

Now a solar panel system yielding 7,300 KWH annually will run about \$28,000 installed, and the system should last 25 years. But 1.5 tons of coal will cost (at \$250 per ton) \$375 per year.

\$28,000/\$375 = 75 years. The solar panels will begin showing their advantage over coal in 75 years. But by then, you would likely have replaced the solar panels and much of the other associated equipment 2 to 3 times.

Just thinking....
lsayre

Stoker Coal Boiler: AHS S130 Coal Gun
Coal Size/Type: Blaschak Anthracite Pea
Other Heating: Resistance Boiler (13.5 KW)

### Re: Solar panels vs. Coal, a matter of perspective?

Coal is going to stay the same price for 75 years? I can bet you paid more every year you were burning. In 75 years, price of coal will be about 10 times what it is now. Also, solar panels put out less the older they are. No maintenance on the panels such as batteries? No cost to install a boiler or elec. baseboard?
mozz

Stoker Coal Boiler: Axeman Anderson 1982 AA-130 Steam

### Re: Solar panels vs. Coal, a matter of perspective?

I'm already paying \$300/ton for my coal and that is triple what it was when I started burning ~10 years ago.

At that rate, I wouldn't be able to afford to burn coal anymore and while it does keep me nice and warm, it doesn't turn any of my lights on.

I understand the comparison, but I'm not sure it's completely apples to apples.
jpete

Hand Fed Coal Stove: Harman Mk II
Coal Size/Type: Stove, Nut, Pea
Other Heating: Dino juice

### Re: Solar panels vs. Coal, a matter of perspective?

It's unfortunate that heat can't be directly converted to electricity, with any reasonable efficiency anyways. The million dollar question is, - how can we do THIS part???

lsayre wrote:Therefore I will state that 1.5 tons of coal = 7,300 KWH of electricity
Lightning

Hand Fed Coal Furnace: Overmodified/Bored out Clayton 1537
Coal Size/Type: Anthracite/Awesome Size

### Re: Solar panels vs. Coal, a matter of perspective?

Maybe the only way is to use electric heat in the scenario, 100% efficient although expensive!
michaelanthony

Hand Fed Coal Stove: Vigilant 2310, gold marc box stove, vogelzang pot belly coat rack
Baseburners & Antiques: Home Sparkle 12
Coal Size/Type: Coal Contractor's stove, a little Kimmels 'nut
Other Heating: Very cold FHA oil furnace

### Re: Solar panels vs. Coal, a matter of perspective?

michaelanthony wrote:Maybe the only way is to use electric heat in the scenario, 100% efficient although expensive!

I absolutely agree partner.. Turning electric to heat might be 100% but turning heat to electric is what, less than 5%?? That's why electric is so expensive.. Now imagaine if we COULD do this..

lsayre wrote:1.5 tons of coal = 7,300 KWH of electricity,
Lightning

Hand Fed Coal Furnace: Overmodified/Bored out Clayton 1537
Coal Size/Type: Anthracite/Awesome Size

### Re: Solar panels vs. Coal, a matter of perspective?

After our oil boiler went on the fritz years ago, our home became all electric (via a resistance boiler). Then we got the coal boiler.

When we were all electric we were using roughly 30,000 KWH of electricity each year, and now we are down to about 7,300 KWH annually. The only difference for us was converting home heat and DHW from electricity to coal, so for me it was a trade of BTU for BTU.

Now I'm trying to figure out how to economically get rid of the bills for the remaining 7,300 KWH of electricity. Everything except heat and DHW is still electric for us. Wish I had NG for the dryer, the stove, and the oven.... I wonder how many KWH we would use annually if that was the case?

What are you other forum members using regarding average annual KWH's of single family residential electricity?
lsayre

Stoker Coal Boiler: AHS S130 Coal Gun
Coal Size/Type: Blaschak Anthracite Pea
Other Heating: Resistance Boiler (13.5 KW)

### Re: Solar panels vs. Coal, a matter of perspective?

I use about 4500 KW a year. Electric water heater is my biggest user, probably half of it. No furnace. very little A/C. My clothes washer is old and uses 800w when running. Fridge uses 250w. I have all those efficient light bulbs except in my kitchen. Not much for outside lighting. I know my electric use is in the lowest 20% of the lowest 20% of my utility company, but lots of farmers is partially why.
warminmn

Hand Fed Coal Stove: Chubby Junior, Efel Nestor Martin, Frankenstove
Coal Size/Type: nut and stove anthracite. Soft coal
Other Heating: wood

### Re: Solar panels vs. Coal, a matter of perspective?

We have electric stove, dryer and hot water tank, not sure of usage, would have to look at a bill. Use NG for backup heat, but Coal about 100% of the time.
I put TIMER (Intermatic) on the Hot water tank so it only heats a few hours in the morning and a couple in the afternoon (do dishes, etc..), it saved about \$20-30/month since it's not cycling all the time.

Depending on your solar setup, I assume Grid Tie system, it can supplement during the day, but if you have some type of storage (off grid) battery bank, it can help even more and reduce your electric bill.
WNY

Hot Air Coal Stoker Stove: Keystoker 90K, Leisure Line Hyfire I
Coal Size/Type: Rice
Stove/Furnace Make: Keystoker, LL & CoalTrol
Stove/Furnace Model: 90K, Hyfire I, VF3000 Soon

### Re: Solar panels vs. Coal, a matter of perspective?

Lightning wrote:
michaelanthony wrote:Maybe the only way is to use electric heat in the scenario, 100% efficient although expensive!

I absolutely agree partner.. Turning electric to heat might be 100% but turning heat to electric is what, less than 5%?? That's why electric is so expensive.. Now imagaine if we COULD do this..

lsayre wrote:1.5 tons of coal = 7,300 KWH of electricity,

Anyone ever fiddle around with using thermocouples/thermopiles to generate some electricity?

I have an old Popular Science from the 50's and they had an adapter to slip over the shade on an oil lamp made from thermocouples that made enough juice to power a transistor radio.

It would probably only work if you already had solar panels and a battery bank. Otherwise it would simply be too cost prohibitive for whatever little you might generate.
jpete

Hand Fed Coal Stove: Harman Mk II
Coal Size/Type: Stove, Nut, Pea
Other Heating: Dino juice

### Re: Solar panels vs. Coal, a matter of perspective?

I converted my sisters summer home from wind (turbine broke) to Solar with a 2 x 230 Watt panels (so far) and a 690aHr battery bank. it is completely off grid, but does have a 6K generator if needed. Its working quite well so far, I have 4 more 255 watt panels to install next spring, so we'll have 1.5kWatt of power. We normally just stay up there on the weekends every so often.
WNY

Hot Air Coal Stoker Stove: Keystoker 90K, Leisure Line Hyfire I
Coal Size/Type: Rice
Stove/Furnace Make: Keystoker, LL & CoalTrol
Stove/Furnace Model: 90K, Hyfire I, VF3000 Soon

### Re: Solar panels vs. Coal, a matter of perspective?

lsayre wrote:What are you other forum members using regarding average annual KWH's of single family residential electricity?

14,000-15,000 kWh per year. Electric clothes drier, three window a/c units in summer, and pool pump are the biggest offenders. Well pump supplies water to two houses. There are two 175w dusk till dawn lights, two refrigerators and an upright freeze (all are <5 yrs old).

Hot water is coal powered, kitchen stove is propane.
Rob R.

Stoker Coal Boiler: EFM DF520
Hand Fed Coal Stove: Hitzer 50-93
Coal Size/Type: Lehigh Rice
Other Heating: Dad's 1953 EFM Highboy

### Re: Solar panels vs. Coal, a matter of perspective?

From November '12 - November '13 we used 7515 ... and that's with a 2 week vacation in September - a rare occurrence, so that number should be 200 or so kWh higher.

Just me and the wife, oil-fired hot water, electric stove & dryer. Biggest users are the dryer, and window A/C units in summer. Have a 160w mercury vapor light on all night. Electric co. says we're on track to use 6% less than last year. Only thing I've done that would effect electric usage is replace my electric eye on the aforementioned light, and face it south instead of north. That cut down on how long the light is lit dramatically ... but I highly doubt a 160w light accounts for 6% of my annual bill ...

If I had solar, I wouldn't have any of this (pic below) .... but I'd have the associated costs of installing solar. 6 of one, half-dozen of the other ... but I'd rather the money went to a panel or battery company than our government - state OR federal!

SMITTY

Stoker Coal Boiler: Patriot Coal - (custom built by Jim Dorsey, Taunton MA - RIP 4/18/13)
Hand Fed Coal Stove: Harman Mark III (SOLD!)
Coal Size/Type: Rice / Blaschak anthracite
Other Heating: Oil fired Burnham boiler

### Re: Solar panels vs. Coal, a matter of perspective?

At some point, solar will be even more cost effective. I sure wish I had a couple banks of panels, for power and heat, BUT.......I have seen many installs and the results are quite satisfying, so blend whatever systems we can to satisfy our hot water, heat, and power needs. I work on two Hydros, and never ask 'why'. It is a no-brainer...and yes the environmental impact on the plants, fish, bunny huggers.......beats the hell out of a nukie going bad!!!!!!!!!!!!!!!!!! You will never get everyone excited about whatever is the latest, greatest, anyway. If it works for you, by all means go for it. Back in the day, there were lots of small windmills that powered electrical generators and pumped water in remote locations around here. Many are still there, power ones are not active, but the water pumps still are. Old solar panels are not worth anything, compared to a 40 year old AA, EFM, GJ, Keystoker, Allen, Walker, Yellow Flame, Van Wert. Even the big boilers from Mills and International are still as good as the day they left the foundry.
Last edited by whistlenut on Mon Dec 02, 2013 5:57 pm, edited 1 time in total.
whistlenut

Stoker Coal Boiler: AA130's,260's, AHS130&260's,EFM900,GJ & V-Wert
Hand Fed Coal Boiler: Franks,Itasca 415,Jensen, NYer 130,Van Wert
Hot Air Coal Stoker Furnace: Alaska, EFM, Keystoker, Yellow Flame
Hot Air Coal Stoker Stove: Alaska, Keystoker-2,Leisure Line
Hand Fed Coal Stove: Alaska, Gibraltar, Keystone,Vc Vigilant 2
Hand Fed Coal Furnace: Ford, Jensen, NYer, Van Wert,
Baseburners & Antiques: Glenwoods
Coal Size/Type: Barley, Buck, Rice ,Nut, Stove
Other Heating: Oil HWBB

### Re: Solar panels vs. Coal, a matter of perspective?

I have been dabbling with wind and solar for the past ten years and have to say the most impressive combo I have hooked up has been two 4x7 hot water solar panels. They circulate through a 30 gallon tank in my basement. If the sun is out they will always heat the tank to 100+ degrees in a days time. General rule of thumb is the tank water will be 100 degrees above the high for the day. I have seen the system heat a tank of water to 110 degrees on a day that the high was 5 degrees, but it was sunny. 30 gallons doesn't sound like a lot of hot water but if use is staggered during the day the system will recover quite fast. I bought the entire system for 300 bucks from a solar guy that was removing it from a house and replacing it with the newer tube system. It is an old setup probably installed in the 70's but worked fine for me the first 5 years after I installed it. The pump has let go and needs replacing which I will be doing next week. Since installing the 130 I have turned into a coal counter and hope that getting the hot water system back on line will ease coal consumption.
I also built a 12' diameter wind mill which would do an average of 40 dollars a month in electricity. It is not grid tied and after cooking 4 banks of batteries I lost interest in the mill. It is a 12 volt system and even though I have the charge controllers, dump loads, furling tail etc. I still seam to cook batteries. My nutshell theory is that batteries are only happy when they are full, they don't like being charged to fast nor drawn fast and I seemed to be doing both with the mill. I think a grid tied mill would be a better solution but the last I knew a grid tied inverter was not available for my mill and if it was I would be forever getting the cost of it back.
I have a small solar system on a summer cabin that consists of a used 50 watt panel, 3000 watt Chinese inverter and two 6 volt golf cart batteries. That system has worked flawlessly and does a fine job of running the cabin lights and recovers well during the day. I have been using this setup for 20 years, have replaced the batteries once and the 50 watt panel works as good now as the day I bought it, and I bought it used as well.
Keving

Stoker Coal Boiler: Axeman Anderson 130
Coal Size/Type: Kimmel pea coal