WetEV
Posts: 2085
Joined: Fri May 04, 2012 8:25 am
Delivery Date: 16 Feb 2014
Location: Near Seattle, WA

Re: Economics of Renewable Power, simplified.

Fri May 19, 2017 11:04 am

RegGuheert wrote:... and can achieve a 70% round-trip efficiency[/url]. That's the kind of performance we need to achieve to make long-term storage a viable possibility.


I disagree.

Long term storage is more driven by cost than efficiency. The opposite of short term storage.

Let me try out an example to illustrate:

$0.10 primary generation from solar cells. 10% ROI + expenses.
Li-ion batteries, $100 per kWh, 90% round trip efficient.
Flow battery, $1 per kWh, 25% efficient.

Cost for a short term storage: assumed to be once per day.

Battery total cost = energy cost + capital cost = 0.10/0.9 + 100*.1/365 = $0.14/kWh
Flow total cost = energy cost + capital cost = 0.10/0.25 + 1*.1/365 = $0.40/kWh

Cost for long term storage: assumed to be once per year.

Battery total cost = energy cost + capital cost = 0.10/0.9 + 100*.1/1 = $10.11/kWh
Flow total cost = energy cost + capital cost = 0.10/0.25 + 1*.1/1 = $0.50/kWh

To build a system with a minimum cost, some fraction of the storage should be low cost (and perhaps low efficiency) and some should be high efficiency and higher cost. Lowest cost will come with some amount of excess generation, enough short term storage to cover daily to a week or so, and some lower efficiency longer term storage.

This is the point to something like hydrogen fuel cells, which is a type of flow battery. Flow batteries are generally not potentially useful for cars, as the potential low cost technologies have low specific energy densities (kWh/mass).
WetEV
#49
Most everything around here is wet during the rainy season. And the rainy season is long.
2012 Leaf SL Red (Totaled)
2014 Leaf SL Red

User avatar
RegGuheert
Posts: 6229
Joined: Mon Mar 19, 2012 4:12 am
Delivery Date: 16 Mar 2012
Leaf Number: 5926
Location: Northern VA

Re: Economics of Renewable Power, simplified.

Fri May 19, 2017 6:02 pm

WetEV wrote:
RegGuheert wrote:... and can achieve a 70% round-trip efficiency[/url]. That's the kind of performance we need to achieve to make long-term storage a viable possibility.
I disagree.

Long term storage is more driven by cost than efficiency. The opposite of short term storage.
Actually, both long-term and short-term storage are driven by cost. (That's why there is virtually no installed storage beyond pumped hydro.) They have different cost drivers, but efficiency is a key driver for both of them.
WetEV wrote:Let me try out an example to illustrate:

$0.10 primary generation from solar cells. 10% ROI + expenses.
Your example fails here. You assumed that the per-kWh cost of generation is the same for every bit of generation which is added. In fact, the per-kWh cost of generation goes up as more is added, since additional generation results in lower-and-lower additional kWh of generation. In the extreme case, once you have enough generation, additional generation has an infinite per-kWh cost since it provides no additional generation. (It may have other value, however, such as redundancy or margin.)

But we CAN readily calculate the relative costs of the low- and high-efficiency long-term storage options since the author of the article I linked provided details of how those two options impact the overall performance of the system. Here are the numbers:

RM = Renewable Methane
RMG = Renewable Mixed Gas

Code: Select all

Component                 No Tier 2      RM       RM Cost      RMG         RMG Cost
-----------------------------------------------------------------------------------
Tier 2 efficiency                        34%                   70%           
Wind                        75 GW       75 GW       $0        72 GW         -$6B
Solar PV                    80 GW       80 GW       $0        75 GW         -$5B
Tier 1 storage             300 GWh     300 GW       $0       200 GWh       -$10B
Tier 1 inverters            60 GW       60 GW       $0        60 GW          $0
Electrolyzers                           40 GW      $20B       30 GW         $15B
Gas turbine generation                  40 GW(Exist)$0
Fuel cells                                                    40 GW        $280B
Tier 2 Storage                      14,000 GWh      $1B   18,000 GWh        $18B
====================================================================================
Total Costs:                                       $21B                    $304B

Cost assumptions:
Wind: $1/W
Solar PV: $2/W
Tier 1 storage: $100/kWh
Electrolyzer: $500/kW
Gas turbine: $3000/kW (But it is already exists!)
SO Fuel cell: $7000/kW
Tier 2 Storage (Natural Gas): Guess: Low since it can be stored in the existing pipelines and storage facilities.
Tier 2 Storage (CO2): Guess: $1/GWh

So this result agrees with your conclusion in that the lower-efficiency solution is cheaper. But the ONLY reason for that is that the natural gas generators already exist as does some of the natural gas storage. I used TODAY'S costs for solid oxide fuel cells. If in 2030, the solid-oxide fuel cells are the same cost or cheaper than natural gas turbines, then the result goes the other way by a long shot for systems that do not already have the gas turbines.

Let's see what the author comes up with regarding the 2030 cost model for these scenarios.
RegGuheert
2011 Leaf SL Demo vehicle
10K miles: Apr 14, 2013, 20K miles (55.7Ah): Aug 7, 2014, 30K miles (52.0Ah): Dec 30, 2015, 40K miles (49.8Ah): Feb 8, 2017, 50K miles (47.2Ah): Dec 7, 2017.
Enphase Inverter Measured MTBF: M190, M215, M250, S280

User avatar
RegGuheert
Posts: 6229
Joined: Mon Mar 19, 2012 4:12 am
Delivery Date: 16 Mar 2012
Leaf Number: 5926
Location: Northern VA

Re: Economics of Renewable Power, simplified.

Sat Aug 19, 2017 10:33 am

RegGuheert wrote:Let's see what the author comes up with regarding the 2030 cost model for these scenarios.
O.K. Here is the author's follow-up post regarding the overall cost to move Texas to renewables by 2030.

Here is his list of projected per kW costs for equipment:

Image

Here is what I had projected:

RegGuheert wrote:Cost assumptions:
Wind: $1/W
Solar PV: $2/W
Tier 1 storage: $100/kWh
Electrolyzer: $500/kW
Gas turbine: $3000/kW (But it is already exists!)
SO Fuel cell: $7000/kW
Tier 2 Storage (Natural Gas): Guess: Low since it can be stored in the existing pipelines and storage facilities.
Tier 2 Storage (CO2): Guess: $1/GWh
So here is where we differed:

- My wind costs matched his high-end wind costs.
- My PV costs were about 3X his PV costs.
- My battery costs were about 2X his battery costs.
- My electrolyzer costs matched his low-end costs.
- My gas storage costs were about 4X his low-end costs.

Anyway, the author did not price the fuel-cell option. Here is what he came up with for system costs using natural gas generators:

Image

The bottom line is that he projects wholesale costs to be between 6.1 c/kWh and 9.2 c/kWh in by the year 2030. If his numbers are in the ballpark, it seems possible that Texas could pull this off. They certainly have a much better chance than Germany of being able to do this.
RegGuheert
2011 Leaf SL Demo vehicle
10K miles: Apr 14, 2013, 20K miles (55.7Ah): Aug 7, 2014, 30K miles (52.0Ah): Dec 30, 2015, 40K miles (49.8Ah): Feb 8, 2017, 50K miles (47.2Ah): Dec 7, 2017.
Enphase Inverter Measured MTBF: M190, M215, M250, S280

Reddy
Posts: 1496
Joined: Fri Feb 11, 2011 3:09 pm
Delivery Date: 18 Aug 2011
Leaf Number: 006828
Location: Pasco, WA

Re: Economics of Renewable Power, simplified.

Tue Aug 22, 2017 2:23 pm

Certainly TX has more solar, and probably more wind, than Germany. If only they would connect more to the US grid and send the excess to adjacent states.
Reddy
2011 SL; 9 bar, 45.80 AHr; 45,000 mi; rcv'd Aug 18, 2011
Long: http://www.mynissanleaf.com/viewtopic.p ... al#p226115"
Cold: http://www.mynissanleaf.com/viewtopic.p ... 60#p243033"

WetEV
Posts: 2085
Joined: Fri May 04, 2012 8:25 am
Delivery Date: 16 Feb 2014
Location: Near Seattle, WA

Re: Economics of Renewable Power, simplified.

Fri Mar 23, 2018 8:38 am

Interesting article in Vox:

https://www.vox.com/energy-and-environm ... researcher

The consensus is emerging that we can probably do 80 percent [renewables] with some combination of spatial diversity and short-duration storage.


For 100 percent, I don’t think we actually know what the right cost-optimal solution is. The seasonal nature of wind and solar is a problem.
WetEV
#49
Most everything around here is wet during the rainy season. And the rainy season is long.
2012 Leaf SL Red (Totaled)
2014 Leaf SL Red

AndyH
Posts: 6384
Joined: Fri Apr 23, 2010 3:43 pm
Location: San Antonio

Re: Economics of Renewable Power, simplified.

Mon Mar 26, 2018 8:47 pm

https://www.cleanenergywire.org/news/renewables-cover-about-100-german-power-use-first-time-ever
Germany has crossed a symbolic milestone in its energy transition by briefly covering around 100 percent of electricity use with renewables for the first time ever on 1 January. In the whole of last year, the world’s fourth largest economy produced a record 36.1 percent of its total power needs with renewable sources.

At around 6:00 am on 1 January, a combination of strong winds and low demand after New Year's Eve celebrations meant that wind power alone produced about 85 percent of Germany’s power consumption, according to data provided by the Federal Network Agency. Hydropower and biomass installations covered the rest, as there was no solar power generation before sunrise.

Given the rapid growth of renewable energies, Germany has already reached its target of increasing their share of power consumption to 35 percent by 2020.






"The stupid become extinct."-Bill Mollison
2018 Outlander PHEV
2015 smart Electric Drive (lease ended Feb, 2018)
OpenEVSE Plus DIY

AndyH
Posts: 6384
Joined: Fri Apr 23, 2010 3:43 pm
Location: San Antonio

Re: Economics of Renewable Power, simplified.

Wed Mar 28, 2018 8:19 pm

WetEV wrote:Interesting article in Vox:

https://www.vox.com/energy-and-environm ... researcher

The consensus is emerging that we can probably do 80 percent [renewables] with some combination of spatial diversity and short-duration storage.


For 100 percent, I don’t think we actually know what the right cost-optimal solution is. The seasonal nature of wind and solar is a problem.

The seasonal nature of wind and solar is only a problem when one accepts paradigms that consider them to be a problem. The TIR process being used in a number of areas combines 100% renewable generation and a long-term storage solution that not only nullifies the seasonality of wind and solar, but of biomass and thus biomethane. And it does this while providing all needed energy of a modern industrial society,

The paradigm/plan/system must be selected before deep-dives into cost estimates are meaningful.
"The stupid become extinct."-Bill Mollison
2018 Outlander PHEV
2015 smart Electric Drive (lease ended Feb, 2018)
OpenEVSE Plus DIY

AndyH
Posts: 6384
Joined: Fri Apr 23, 2010 3:43 pm
Location: San Antonio

Re: Economics of Renewable Power, simplified.

Mon Apr 09, 2018 7:57 am

https://reneweconomy.com.au/portugal-reaches-100-renewables-ends-fossil-fuel-subsidies-32820/
Portugal’s renewable energy sources generated enough power to exceed total grid demand across the month of March, a new report has found, setting a standard that is expected to become the norm for the European nation.

...

The achievement comes nearly one year after hydro, wind, and solar power helped push the Iberian country to run on 100 per cent renewable electricity for 107 hours straight. Last March, however, the average renewables supply was 62 per cent.

The new record coincides with the move by the Portuguese government, last Tuesday, to suspend annual subsidies of around €20 million for guaranteed power supplies paid to producers – most of which goes to fossil fuel plants left in stand-by mode.


While fossil-fueled pundits in the US say it can't be done, the rest of the world is doing it. Move along - nothing to see here. :lol:
"The stupid become extinct."-Bill Mollison
2018 Outlander PHEV
2015 smart Electric Drive (lease ended Feb, 2018)
OpenEVSE Plus DIY

Return to “Business / Economy and Politics”