Climate Change / Global Warming Discussion

[rays427]

Beeeerock,

I calculated my cost to go total solar as 10 times what I paid for my 20 year lease divided by the guaranteed total Kwh for 20 years. The reason for this is my system during the summer produces much more than I need but produces only about 1/10 of my use in the winter. So to use only solar would require me to have a system about 10 times what I now have. This doesn't include converting my furnace, stove, dryer and water heater to electric. Now I know that a larger system would cost less but this just offsets my need to convert heating, etc from propane. I would also need to buy a storage systme to handle night time use and the worst production days in the winter. My actual daily production has varied from 1 Kwh to 63 Kwh. Monthly my low was 216 Kwh and high should be about 1800 Kwh this month.

 

[nwdiver]

Beeeerock,
The reason for this is my system during the summer produces much more than I need but produces only about 1/10 of my use in the winter.

Do you have heavy shading to your south that only effects your winter production? 1:10 winter vs summer seems VERY high for so far south... My house in Bremerton WA is 1:9; My house in NM is ~1:2. I agree that seasonal changes in solar insolation will be challenging but large scale wind farms should be able to help with that. Wind tends to be more productive in the winter. Wind + Solar... it's like it was meant to be :love:

 

[Robert.Boston]

Beeeerock,

I calculated my cost to go total solar as 10 times what I paid for my 20 year lease divided by the guaranteed total Kwh for 20 years. The reason for this is my system during the summer produces much more than I need but produces only about 1/10 of my use in the winter. So to use only solar would require me to have a system about 10 times what I now have. This doesn't include converting my furnace, stove, dryer and water heater to electric. Now I know that a larger system would cost less but this just offsets my need to convert heating, etc from propane. I would also need to buy a storage systme to handle night time use and the worst production days in the winter. My actual daily production has varied from 1 Kwh to 63 Kwh. Monthly my low was 216 Kwh and high should be about 1800 Kwh this month.

What you are calculating, therefore, is the cost for you to go standalone solar. That's going to be expensive; it's also unnecessary. Use the grid. The grid opens up diversity of supply and demand.

On the supply side, we'll have a combination of hydro, solar, wind, and marine energy, possible augmented by nuclear. We'll have centralized and distributed storage. Combining all these assets, and I'm confident that the wholesale power cost (including capital recovery) will be under 10¢/kWh, which is only a modest increase over the levelized cost of new fossil-fueled plant. As tech keeps improving, that cost will continue to drop.

On the demand side, by combining many customers and adding demand-side automatic load controls, we'll be able to do a lot of renewables integration even without storage, just by deferring demand by minutes or hours.

Also, remember that building new fossil-fired plants isn't free, and a lot of what we use today in the U.S. is getting very old, dating back to the Korean War. The modest goal should be, stop building new ones, or limit those builds to reliability-must-run units (places you really have to have voltage support).

 

[rays427]

Well I took a look at my propane use to see how much electricity I would need to replace it. I used about 200 gallons per month in the highest 3 months. That's equivalent to 5400 Khw per month. If you include my electric use in the highest month my total would be around 7200 Kwh per month. The output in that month from my system ($22,000 for 20 year 12KW lease) was 216 Kwh (7.2Kwh average per day with low of 1). So I would need 33 times what my current system puts out. Now I'm sure that a utility scale solar system would do better than my system especially including wind, nuclear, hydro, geothermal, etc but it still would be prohibitively expensive to cover my winter time needs without fossil fuels. The utility would not only need to produce 33 times my system but would also have to install storage and upgrade the transmission system if everyone converted to electric only.

The reason my system is economic is that it displaces the higher tier PG&E rates. Since converting to the EV-A rate in mid January and my monthly bills have varied from +$283 February to -$240 this month. The minus $240 resulted from being out of town for a good part of the month but it would have been around -$150 if we were home the whole time. I'm very happy with my solar system and think we need to install a lot more wind, solar, nuclear, geothermal, hydro etc. but I don't see any way that we can afford to replace most fossil fuels with current technology.

 

[CalDreamin]

The reason my system is economic is that it displaces the higher tier PG&E rates. Since converting to the EV-A rate in mid January and my monthly bills have varied from +$283 February to -$240 this month. The minus $240 resulted from being out of town for a good part of the month but it would have been around -$150 if we were home the whole time. I'm very happy with my solar system and think we need to install a lot more wind, solar, nuclear, geothermal, hydro etc. but I don't see any way that we can afford to replace most fossil fuels with current technology.

For electricity, the way it's happening is through California's 33% Renewable Portfolio Standard (RPS) mandate. The state's utility scale solar already produces more MWh per day than the combined output of the state's hundreds of thousands of distributed solar such as your and my rooftop PV systems. Utility scale solar has produced about 8% of daily grid demand recently, while RPS renewables combined total about 25%. Solar might double within 5 years when the state hits its 33% RPS mandate. After that, utility scale solar might almost double again to achieve a recently announced 50% RPS mandate by 2030. Beyond 33% RPS, large scale demand response and storage will probably be required.

Over the same time, fossil fuels will be facing increasingly higher costs due to California's GHG law. This will drive up costs of your propane, as well as gasoline, diesel, jet, natural gas, and other fossil fuels.

 

[rays427]

I agree that you can mandate increase in renewables but that doesn't mean it will be economic. The cost of fossil fuels will go up not only as it's taxed more per the GHG law but also as you displace it the fossil fuel plants will still needed to meet winter demand but may not be needed in the summer. Maintaining the plants to produce energy for only a few months a year will make it extremely expensive. Which will then drive towards adding more and more solar and wind until they can meet winter demand. If only California does this the cost of energy here will make California industry uncompetitive. I guess this might really solve the problem since if you can't find a job then mass exodus will help reduce California's fossil fuel use.

 

[CalDreamin]

Nobody is going to keep oil refineries around only for making a low volume / low value product like propane for heating homes. Oil refineries already do their best to minimize their propane yield. Your propane won't be cheap when the cost to produce it is no longer subsidized by the income refiners make selling gasoline, jet, and diesel.

Jobs will increase with the transition to renewables away from fossil fuels. That being said, the business I work in (oil) will have far fewer jobs.

As far as the cost of electricity, the nation's most expensive electricity in recent years has been Hawaii because most of it's made with oil.

The nation's least expensive electricity has been hydropower in the PNW -- a renewable.

Under the RPS mandate, California utilites have the choice to acquire more geothermal, wind, solar thermal, solar PV, biomass, biogas, or small hydro. They can pick whichever is most economic. At one point wind was winning most new utility scale contracts, but now solar PV is the cheapest and is winning.

 

[nwdiver]

Well I took a look at my propane use to see how much electricity I would need to replace it. I used about 200 gallons per month in the highest 3 months. That's equivalent to 5400 Khw per month.

... Ah.... there's your problem; For one you can't do a raw energy comparison like that. An ice that gets ~30mpg needs ~225kWh to travel 200 miles... but an EV doesn't need a 225kWh battery to get the same range because EVs aren't RIDICULOUSLY inefficient.

I'm assuming you use that propane for heat. Unless you have a condensing furnace ~20% of your propane is going to heat your neighborhood. A good electric heat pump on the other hand usually has a COP of ~4. Meaning that you get 4 units of heat for every 1 unit of 'fuel' instead of 0.8 by burning propane.

So basically if you swapped out your propane furnace for a ~SEER 18 heat pump you would only use ~1000kWh(electricity)/mo... not ~5000kWH(propane)

 

[Robert.Boston]

Two points:

* PG&E's tiered rates don't reflect the real marginal cost of electricity; it's a structure that was intended to achieve several goals, including conservation and redistribution of system fixed costs to wealthier homeowners.

* Don't underestimate the value of diversified power sources. Not all sources of renewable power are summer-peaking. For example, wave energy is much better in the winter than summer; I don't offhand know California's seasonal wind pattern, but here in New England, there's more wind energy in the winter in most locations. Here's an estimate of the pattern of wave production offshore of the central coast:

 

[rays427]

You also need to get approval to install all the renewables. I know the company I worked for tried to install wage generation off the coast of California but environmental concerns prevented the installation. Same thing has happened to some wind and solar farms. Good luck on getting new dams built. Natural gas is even cheaper than propane but I agree propane and natural gas will become extremely expensive if the majority of heating and transportation is handled by renewables. However my contention is the renewables will also be very expensive. If 85% is from wind and solar you will need a huge oversupply in the summer to handle the winter needs. You will also need massive storage systems to handle day to night and extremely low output periods. All of this will add to the cost. As long as folks are willing to pay the bill it can work. However if other locations continue to use cheaper energy then good luck on being competitive.

 

[nwdiver]

If 85% is from wind and solar you will need a huge oversupply in the summer to handle the winter needs.

Are you even reading the responses to your posts? Wind and Solar have opposite peaks. Wind peaks at night... Solar obviously peaks during the day. Wind peaks in the winter... Solar peaks in the summer. With sufficient on-site storage you can't be denied a permit to PRODUCE energy from solar... the utility can only refuse your request to EXPORT it... even then those cases are VERY rare. The only place I'm aware of that is refusing inter-connects for Solar PV is Hawaii and the utility has largely lost that battle.

PLUS you're apparently wrong on ALL counts... not only do wind and solar largely COMPLIMENT each other... not COMPETE... electricity consumption NATIONALLY actually peaks in the SUMMER... not the WINTER. (This is probably one of the few areas where climate change is going to help...)Yes, this would obviously shift as more homes are heated with electrically driven HEAT PUMPS but again, wind is MUCH more productive in the winter months, the main reason I'm a HUGE advocate of staying on the grid but still serving as a distributed generator.

So... to recap

- Wind in the Winter / Night
- Solar in the Summer / Daylight
- Storage to fill the gaps
- EVs to soak up the excess :wink:

If we have SIGNIFICANT overcapacity then there's always electrolysis... rockets will always need Hydrogen; Sorry Toyota, Fool cells are still decades away if ever.

 

[rays427]

nwdiver,

I have read all the responses to my posts. Current consumption of electricity peaks in summer because of air conditioning. However if all heating was converted to electricity that would probably change. It certainly would in my case. I agree that solar and wind tend to compliment each other. However I just looked at the eia national wind generation seasonal patterns and it shows that in January and December the annual wind generation is at the median output which is 30% of plant capacity. It peaks in April at about 38% and is at the lowest in July and August at about 22%. Wind generation varies between regions and in California actually peaks in summer. Since solar output is lowest in January and December it's not going to be offset by wind generation. So I still contend that you need quite a bit of oversupply to handle the demand in Winter. This is especially the case in California where wind peaks in winter.

 

[nwdiver]

So I still contend that you need quite a bit of oversupply to handle the demand in Winter. This is especially the case in California where wind peaks in winter.

What's your definition of 'quite a bit'? It's looking like if we wanted 100% renewables in the winter that summer curtailment would only be ~20%... and that's decades away. There are several 'natural' and planned factors that can greatly mitigate summer curtailment with a robust grid.

- We usually drive >10% more in the summer;
- Planned maintenance can be scheduled for summer months to ensure full capacity in the winter
- High energy manufacturing like Aluminum smelting and electrolysis would become more 'seasonal'

Just to name a few; Current solar PV production curves aren't a good indicator of what it could look like with the proper market signals. Most utilities still reward quantity over quality. For example... in NM with net-metering there is ZERO economic incentive to alter the facing of an array to maximize generation to match consumption. My recent project in Texas will be at a higher angle to maximize winter production and west facing to match consumption curves at the expense of total annual production; this actually makes sense in TX since there are no net metering laws.


Is your point that 100% is going to be difficult? Or is your point that it's going to be prohibitively expensive? My point is that it's inevitable and we'll find ways to make it work.

 

[Robert.Boston]

People may not realize that we also have to overbuild the current bulk power system. In most areas, the legally required overbuild is about 15 percent of the forecast peak. Why? Uncertainty. There are two primary sources of uncertainty in the traditional grid: the level of peak load, and the availability of generation resources.

The modern grid is addressing both sides of uncertainty.

Re demand: In the 20th century, nearly all load was uncontrolled: customers flipped the switch, and power was expected to flow. In the 21st century, the "Internet of things" allows an increasing fraction of demand to synchronize with the grid, allowing dynamic response to scarcity. Thus, uncertainty about the peaks can now be managed, to some degree. And that degree is increasing over time.

Re supply: Each control area (e.g. New England) is required to maintain enough reserves to recover from the largest contingency on the system. Some areas have a tighter standard, requiring recovery from "1+1" contingencies (one bad thing happens, and then 10 minutes later, another bad thing happens) or even double contingencies (two bad things happen simultaneously). Any guesses what the largest contingency is in every control area? It's the loss of a big generator (sometimes nuclear, sometimes fossil). In shifting from big, central generators to small, distributed renewables, we trade one contingency for another. We replace one risk (loss of a big coal unit) with a different risk (low winds or a cloudy day). The big difference? You can't predict when a big generator is going to trip off-line, but you can predict the weather.

Bottom line: in shifting to renewables, we are changing what risks we face. We're not just adding uncertainty to the system.

 

[TheTalkingMule]

My new favorite global warming animation.

134 years of average global temps @ Bloomberg

 

[beeeerock]

Bottom line: in shifting to renewables, we are changing what risks we face. We're not just adding uncertainty to the system.

I'd go one step further and say that the distributed model adds redundancy and security to the grid in general. Much like storing data in the Cloud, with redundancy across many servers located in different corners of the planet, having multiple power sources increases the utility's ability to re-route power when a localized problem would otherwise bring down a large piece of the system.

 

[rays427]

I believe it will be extremely expensive to replace all fossil fuels especially when you include all energy requirements. Per the US Energy Information Administration total US Energy Consumption for 2014 converted to Billion Kwh is as follows: Fossil Fuels 23546.5 (81.6%), Nuclear 2440.99 (8.46%), Hydro 723.59 (.23%), Geothermal 65.06 (.23%), Solar/PV 125.14 (.43%), Wind 508.19 (1.76%), Biomass 1397.95 (4.84%) Total Renewable 2819.93 (9.77%), Total 28855.48. So we have a long way to go to replace all fossil fuels. When you add all energy needs the highest demand is in January, February and December. So if everything is converted to electricity the highest demand is when solar is least productive. Wind can make up some of that but since in general it produces more in the winter but again you could have a low solar and wind event on the same day or days. The largest fossil fuel generator is about 20 billion Kwh per year which is .07% of the yearly energy demand. Both Fossil fuel plants and renewables must have enough oversupply to take care of random shutdowns. All energy production can plan maintenance to reduce impact on supply needs. Fossil fuel reduction do to unplanned shutdowns is random. However wind and solar are at the mercy of the weather. Added together they still will provide much less energy in the summer than the winter. The EIA gives the following average capacity factors for common energy sources: Coal 65%, Natural Gas 50%, Nuclear 90%, Wind 30%, Solar PV 20%, Solar Thermal 24%, Hydro 40% and Geothermal 70%. As you can see the least reliable are Solar and Wind. I was really surprised by the low capacity factor for Hydro. I would have thought that would be extremely reliable. The problem is that it's also dependent on the weather. If it doesn't rain enough it loses capacity. The largest installed capacity source of power in the US is the Grand Coulee Hydro Station. Last year it only produced about half of what it's capable because of lower rainfall. Please note that Nuclear is by far the most reliable. Not only does wind and solar have the lowest capacity factors they will provide the least amount of power when we need the most energy. Since it seems unlikely that we can add a lot more Hydro or geothermal most additional renewables will need to come from biofuels, solar and wind. Since biofuels emit co2, wind and solar will need to provide most of the additional power if your goal is to reduce co2. So to provide enough capacity to provide the needed power in the winter you will need a lot of additional capacity and large scale electric storage systems to provide power during the days of low wind and solar production. So I think that with current technology the cost to convert all power to renewables is uneconomic. Nuclear could probably replace all fossil fuels but good luck on getting it approved. Another factor working against replacing all fossil fuels is getting permits for the installation of renewables and required smart grid. All forms of energy production have some negative consequences. Many environmental folks even fight against renewable energy projects. They kill birds, lizards, etc. It all depends on your view of protecting the environment. There are those that think any change do to man is unthinkable. I like the idea of using technology and energy to improve mans quality of life. The life style we now enjoy is mainly due to cheap reliable energy.

 

[Robert.Boston]

@rays427: care is needed in looking at current energy inputs. Inefficient combustion means that fully half of the BTUs we put into coal/oil/gas for electric generation are lost. So if the stats you're relying on measure energy inputs, you can (roughly) halve the figure to get to the electrical energy needed.

Also remember that we lose about 6% of power from transmission losses. As we shift to distributed sources, losses will fall.

Another thing to keep in mind is that technology on the demand side is helping tremendously. E.g., a modern LED light uses about 5% of the energy to match an incandescent light.

 

[rays427]

Robert.Boston,

Great catch. With inefficient combustion the amount of energy needed in the winter will end up about the same as what is needed in the summer. However, I think the amount of transmission losses may even be higher since the weather in an area could cut the amount of energy being produced by wind and solar to near zero, requiring energy being imported from an area with better sun and wind conditions. This would reduce the need for mass electric storage. However quite a bit of mass electric storage will be needed and they are currently very expensive. Changing to LED lights etc will help but at the same time the world need for energy will continue to grow. So overall we will probably need more rather than less energy in the future.

 

[nwdiver]

Another factor working against replacing all fossil fuels is getting permits for the installation of renewables and required smart grid. All forms of energy production have some negative consequences. Many environmental folks even fight against renewable energy projects. They kill birds, lizards, etc. It all depends on your view of protecting the environment. There are those that think any change do to man is unthinkable. I like the idea of using technology and energy to improve mans quality of life. The life style we now enjoy is mainly due to cheap reliable energy.

Even if it is 'extremely' expensive (it's not) to shift away from fossil fuels... that's still MUCH cheaper than the 'prohibitive' cost of continued reliance on fossil fuels. Most of the cost of our addiction doesn't show up on your electric bill.

Fortunately much of the transition will pay for itself in <10 years; It's cheaper to transmit power feet than it is miles; Solar PV is <$2/w (~$0.04/kWh) heading to <$1/w (~$0.02/kWh) by 2020.

You're looking at the future 21st century grid through the lens of the 20th century; Supply blindly matching Demand; The 'Smart Grid' isn't some enormous infrastructure that needs to be 'built' it's largely going to be software. We're transitioning from an era where most energy is generated as it's required to a new paradigm where most energy is used when it's available. This is FAR less intrusive than it sound. Two everyday examples are hot water heaters and electric cars... I couldn't care less when my water is heated or when my car is charged so long as hot water and a charged car are there when I need them. Many energy intensive applications can choose when they are used without even being noticeable.

The life style we now enjoy is mainly due to cheap reliable energy.

Agreed; There is no source cheaper, more abundant or more reliable than the sun.