Impact of battery efficiency on cost - Revision history

Syk0saje: Redirected page to Impact of battery characteristics on off grid system cost

2012-01-28T07:59:42Z

Redirected page to Impact of battery characteristics on off grid system cost

← Older revision		Revision as of 07:59, 28 January 2012
Line 1:		Line 1:
	#redirect [[~~Battery Cost~~]]		#redirect [[Impact of battery characteristics on off grid system cost]]

Chris F: Redirected page to Battery Cost

2011-09-20T14:24:04Z

Redirected page to Battery Cost

← Older revision		Revision as of 14:24, 20 September 2011
Line 1:		Line 1:
	~~{{breadcrumb\|Energy\|Power quality}}~~		#redirect [[Battery Cost]]

	~~Nife batteries are relatively inefficient. To decide on how important an impact this has on cost let's do some reckoning:~~

	~~The Efficiency compensated equivalent cost needs to be estimated calculated for various batteries, I define this as the effective cost per Wh of battery in a solar power system:~~

	~~Basically we need to know how much energy the battery wastes, and the find the cost of that and add that to the sticker price of the battery.~~


	It's the total energy that needs to be withdrawn from the socket by the user plus the energy wasted by the battery, which is the total energy the array needs to supply, divided by the array cost per unit energy, minus what the cost woudl be if the battery was 100% efficient.

	~~Es=Wh that must be delivered/day to socket~~
	~~Ea= Wh delivered per day by the solar array/watt of array~~
	~~EFb= Efficiency of battery charge/discharge overall~~
	~~Cc=cost of collector, in $/watt.~~
	~~Fsib=fraction of the energy that gets to the socket that had to be stored in the battery~~


	~~Cb= cost of battery per Wh of storage~~

	~~ECc=efficiency compensated cost per Wh of battery~~

	~~Cabbi=Total cost added by battery inefficiency~~


	~~Cabbi=((Es+(((FsibEs)/EFb)-FsibEs))Cc/Ea)-CcEs/Ea~~


	~~then~~
	~~(Cabbi/(Fsib*Es))+Cb=ECc~~

	Cost ~~added per Wh of battery storage needed by the system, plus cost of battery per Wh.~~

	~~So if~~
	~~Es=1000Wh~~
	~~Ea= 5Wh/watt~~
	~~EFb= 0.65~~
	~~Cc= $2/watt~~
	~~Fsib= 0.5~~


	~~Cb= $0.2~~


	~~Cabbi=((1000+(((0.51000)/0.65)-0.51000))2/5)-21000/5~~

	~~Cabbi=507.69-400 =107.69~~

	~~(107.69/0.5*1000)+0.2= 0.415~~

	It more than doubles the effective cost of the battery for Nife. Lithium iron phosphate batteries are already available at $0.4 per watt, but only 80-90 percent efficiency they are only just inferior according to wikipedia (might be higher, remember hearing it was, should check battery handbook) search ebay for "thundersky lithium". And they have cycle durability in the same range as nife :http://evolveelectrics.com/Thunder%20Sky%20Lithium%20Batteries.html

	But if the cost of the nife batteries was $0.1 per Wh then we'd be ahead of the game even with the low efficiency. Plus the cost of collectors is going to go down, probably a lot faster than the cost of batteries. Indeed the cost of batteries may well increase substantially, especially lithium batteries, due to market fluctuations or the cost of materials, especially lithium which is coming into huge demand. With zinc bromide we might get the best of both worlds, producing an exceptionally cheap system.

Syk0 saje at 13:11, 25 May 2011

2011-05-25T13:11:29Z

← Older revision		Revision as of 13:11, 25 May 2011
Line 1:		Line 1:
			{{breadcrumb\|Energy\|Power quality}}

	Nife batteries are relatively inefficient. To decide on how important an impact this has on cost let's do some reckoning:		Nife batteries are relatively inefficient. To decide on how important an impact this has on cost let's do some reckoning:

Gregortheinventor: Created page with "Nife batteries are relatively inefficient. To decide on how important an impact this has on cost let's do some reckoning: The Efficiency compensated equivalent cost needs to be..."

2011-05-24T19:24:39Z

Created page with "Nife batteries are relatively inefficient. To decide on how important an impact this has on cost let's do some reckoning: The Efficiency compensated equivalent cost needs to be..."

New page

Nife batteries are relatively inefficient. To decide on how important an impact this has on cost let's do some reckoning:

The Efficiency compensated equivalent cost needs to be estimated calculated for various batteries, I define this as the effective cost per Wh of battery in a solar power system:

Basically we need to know how much energy the battery wastes, and the find the cost of that and add that to the sticker price of the battery.

It's the total energy that needs to be withdrawn from the socket by the user plus the energy wasted by the battery, which is the total energy the array needs to supply, divided by the array cost per unit energy, minus what the cost woudl be if the battery was 100% efficient.

Es=Wh that must be delivered/day to socket
Ea= Wh delivered per day by the solar array/watt of array
EFb= Efficiency of battery charge/discharge overall
Cc=cost of collector, in $/watt.
Fsib=fraction of the energy that gets to the socket that had to be stored in the battery

Cb= cost of battery per Wh of storage

ECc=efficiency compensated cost per Wh of battery

Cabbi=Total cost added by battery inefficiency

Cabbi=((Es+(((Fsib*Es)/EFb)-Fsib*Es))*Cc/Ea)-Cc*Es/Ea

then
(Cabbi/(Fsib*Es))+Cb=ECc

Cost added per Wh of battery storage needed by the system, plus cost of battery per Wh.

So if
Es=1000Wh
Ea= 5Wh/watt
EFb= 0.65
Cc= $2/watt
Fsib= 0.5

Cb= $0.2

Cabbi=((1000+(((0.5*1000)/0.65)-0.5*1000))*2/5)-2*1000/5

Cabbi=507.69-400 =107.69

(107.69/0.5*1000)+0.2= 0.415

It more than doubles the effective cost of the battery for Nife. Lithium iron phosphate batteries are already available at $0.4 per watt, but only 80-90 percent efficiency they are only just inferior according to wikipedia (might be higher, remember hearing it was, should check battery handbook) search ebay for "thundersky lithium". And they have cycle durability in the same range as nife :http://evolveelectrics.com/Thunder%20Sky%20Lithium%20Batteries.html

But if the cost of the nife batteries was $0.1 per Wh then we'd be ahead of the game even with the low efficiency. Plus the cost of collectors is going to go down, probably a lot faster than the cost of batteries. Indeed the cost of batteries may well increase substantially, especially lithium batteries, due to market fluctuations or the cost of materials, especially lithium which is coming into huge demand. With zinc bromide we might get the best of both worlds, producing an exceptionally cheap system.