From the BayareaEnergyForum archive 12/2014 By Bob Owen
Comments on Stanford Study and Wisconsin It is useful to think about all-renewable scenarios even if we disagree with the particular approach taken at Stanford. I partly disagree with the Stanford approach in Wisconsin, but I do agree that neither new nuclear nor natural gas extracted from the ground ought to be part of any post-2040 strategy for the reasons expressed by the Stanford group. Nuclear is cleaner than natural gas, if we are talking about existing plants like Point Beach and Kewaunee, but neither nuclear plant will be available post 2040. It is certainly possible to get completely off fossil fuel, and we don’t have to wait until 2050 to do it. We already have the technology to do it, although it would be nice to further refine offshore wind and battery technology to increase cost effectiveness. The Stanford group projects the following clean energy sources for Wisconsin in 2050: Inland wind 45% Offshore wind 30 Solar 24 Hydro 1 The Stanford group projects no sustainable biomass. I think that’s foolish in our state, although I do agree that large-scale ethanol is not desirable in a clean-energy system. I think we could definitely use biomass like wood pellets and hay and reed canary grass and biogas cleanly, sustainably and cost-effectively in fairly large amounts. I think we could use moderate amounts of cellulosic ethanol, propanol and vegetable oil produced in a sustainable manner on our farms. I think Stanford gives too much emphasis to inland wind in Wisconsin’s clean energy mix. If I were doing my own scenario, I would suggest terminating fossil fuels by 2040 in favor of the following: Inland wind 30% Offshore wind 25 Solar 25 Wood biomass 7 Farm liquid bio-fuels 5 Hay, canary grass 3 Farm bio-gas 3 Landfill and other natural methane 1 Hydro 1 Adding biomass judiciously to the mix would reduce the need for battery energy storage and reduce costs without increasing carbon emissions. 2040 is a long way off. Some of us may be making a much quicker transition to renew- able energy in the next few years. There has been an up-tick in business for off-grid solar companies in recent months in S. Wisconsin in reaction to recent utility rate change pro- posals. Now that those proposals have largely been approved by the PSC, interest in off- grid options is likely to continue to increase. And it will increase even more if the utilities do not relent on their plans to radically increase fixed charges after 2015. So, yes, in response to Tom’s suggestion, we will need batteries if we go off grid (and, even if we do not, the grid is likely to need more batteries or pumped-hydro storage or other energy storage facilities as wind energy gets to be a larger percentage of the energy on the grid). If we go off grid, we will likely have batteries in our basements. Increasing- ly, if we want to get off oil, we will have mobile batteries in our garages in the form of EVs. Largely charged at night, EVs will be mostly wind powered. A rough rule of thumb for off-grid systems is to have about three days of working storage to handle fluctuations in solar availability. Thus, if you use 300 kWh per month, a fairly modest amount of electricity, you need about 30 kWh of working battery storage. That means you actually need about 60 kWh of batteries costing about $10,000 for common lead-acid deep-cycle batteries because typically you don’t want to discharge those batteries more than 50 percent to try to get a reasonable life (7 or 8 years typically if well maintained) from your battery investment. While solar panels are getting pretty reasonable in cost, batteries are still pricey. The same is true of other kinds of batteries such as the lithium-ion batteries used in EVs and flow batteries that utilities could use for larger-scale grid energy storage. The good thing about batteries is that these costs are likely to come down. So, if you would go off grid in 2015 and pay a lot for batteries to do it, you would pay less when you replace those batteries in 2022 or 2023. By then, your off-grid system would likely cost less than grid electric service from the likes of MGE and We Energies. And the only big thing you would need to replace in 2022 or 2023 would be batteries. The rest of the system would last at least another 20 years. However, there is another energy storage technology which could be used for large-scale, seasonal, energy storage. We could store temporary surplus wind energy seasonally by making anhydrous ammonia (NH3) from water and air and storing it as we now store fertilizer. We could then either reform the ammonia to release hydrogen, which we can use to operate engines or fuel cells or heating appliances, or use the ammonia directly as fuel in engines when we need more electricity. Long term energy storage is costly, but we do not need fossil fuels to keep the lights on on hot, calm, days. We can do that with renewable energy stored in the form of ammonia or hydrogen. Having Wisconsin well connected to surrounding states by high-capacity transmission lines would also somewhat reduce the need for battery energy storage in Wisconsin be- cause wind is always blowing somewhere in the Midwest even if not in our state at the An all-renewable energy system would convert most transport to electric energy. EVs would be the rule. Trains would be electrified and carry most long-distance cargo and passengers not riding in EVs. Air travel would increase in cost and virtually disappear except for transoceanic travel. Electric trucks would do short-range deliveries. In an all-renewable energy system, we could replace rural propane use with biomass. We could replace urban natural gas with hydrogen created in the fall and winter from surplus offshore wind energy from Lake Michigan wind farms. That hydrogen could also power some transport which could not be electrified (including transoceanic aircraft). We can operate an efficient modern economy with 100% clean energy. Costs can be affordable. The planet can be habitable or not. An uninhabitable planet is not affordable on any rational scale. We just need to decide soon to make the commitment to be carbon free or to respond rationally to a revenue-neutral carbon fee and dividend high enough to get us to our goal. Robert Owen 12/5/14 Stanford study link :
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