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On Comparison of Grid-Connected and Off-the-Grid Houses

Willem, I too have been studying and analyzing distributed power and energy systems over the years.  A few issues caught my attention in reviewing your Post that you might want to consider addressing in the future:

·         The efficiency of solar PV low voltage DC to 110V AC power ‘inverters’ are normally in the 80-90% range.  Generally only industrial scale inverters have higher efficiencies compared to average inverters installed with Residential solar PV systems.  This factor also decreases the capacity factor of a given solar PV panel array system (max. design generation).

·         The same 80-90% efficiency range generally applies to 110V AC to 12-24V DC power ‘converters’ for most EV chargers.  I am sure you are aware the most efficient systems are 220-440V AC EV chargers; which also minimizes charging cycle times.  Also, the somewhat popular/perceived technology of using EV batteries to supply the centralized Power Grids repeats these energy conversion loss levels twice; which makes the practicality of this technology approach to backup power for variable wind power highly questionable.

·         Most ‘off-the-grid’ Residences that require or desire reasonable reliable power 24-7-365 also install backup generators; petroleum or natural gas motor fuels.  Even a multi-ton Residential battery system will be inadequate in different geographic locations and times of the year.  Based on personal experience, Bellingham, Washington was subjected to 90 consecutive (cloudy) days without the sun one year.  Without backup generators, you will be in the dark much of the time in many locations around the world.

·         The most efficient Residence, besides insulation, sealing, orientation to the sun, etc. also requires major behavior adjustments to not over heat the house during the winter, over cool it during the summer, efficiently manage external-internal air exchange, not waste hot water, etc.  Most of these systems can be automated including external air exchange, but the critical variable is how the Resident programs the system to minimize energy waste.  This generally means wearing a sweater in the house during the winter and shorts/’T’ shirt during the summer.  And, of course, as Mom use to tell us as kids, “turn out the lights” (when not needed).  Even this function can be automated (motion-timer switches more commonly found in some Commercial Buildings).

November 26, 2014    View Comment    

On Energy Quotes of the Day: On the EPA's RFS Ineptitude

Renewable Fuels Association (RFA) quote: “Not making a decision is not a decision”?  Really.  When you are in the Refining and/or Blending Business you normally plan your operations annually, beginning well before the first of the year.  Operating plans/budgets normally involve scheduling the purchase of feed and blend stocks, including ethanol, many months up to a year in advance of actual blending/sales/transportation into the Retail markets.  So what’s the big deal with the EPA delaying the RFS blending requirements for 2015 past the first of the year?  Besides making it difficult-to-nearly impossible to plan ahead and reasonably/efficiently optimize one’s operations, this “non-decision” makes commitments for longer term supply purchases or contracting for unknown levels of ethanol blending fairly risky.   How is a Refiner/Blender expected to manage their operations efficiently including purchasing ethanol and/or RIN’s and petroleum gasoline blend stocks to comply with an unknown RFS blending level not finalized by the EPA until after the fact?  The EPA’s ‘non-decision’ directionally forces Refiners/Blenders to delay these actions needed to comply with RFS requirements and minimize costs, and puts future profit margins at risk.

So, why would the RFA care if a decisions was made or not?  Their membership of Ethanol Producers might care, since they will also be negatively impacted by being unable to plan their future operations; similar to Refiners/Blenders.

November 25, 2014    View Comment    

On Keystone XL Loses Another Round

Geoffrey, what the Environmentalist-fund raisers have overlooked is the fact that Canadian crude oil imports have still increased by about 1.0 million barrels per day (MBD) over the past four years, or greater than the capacity of the proposed-delayed Keystone XL (phase two) pipeline project.  These imports have been transported by a combination of the completed Keystone XL phase one pipeline project, cross-border rail, followed by marine and truck in some cases.  With the exception of the Keystone XL phase one project (completed in 2010 and probably not identified by those opposed to the phase two project), all the currently used alternative modes of transport are much less efficient and have higher transport risks than pipelines.

November 24, 2014    View Comment    

On Keystone XL Loses Another Round

Geoffrey, as I am sure you are aware, President Obama will most likely never approve the Keystone XL pipeline.  If indeed he believes the pipeline is not in the best interests of the Country, he should have made a final decision to ‘not approve the project’ years ago.  Fortunately for him, Harry Reid has blocked all Senate actions over the past 6 years, and likely would have not brought the recent bill to the floor unless he was very sure the Democrats would not approve it.  The decision to continuously ‘not make a decision’ on the pipeline obviously is in support the President’s party/environmental base, (i.e. those who oppose the pipeline period!, regardless of the relevant facts), and some will continue to financially benefit without the Keystone XL pipeline, primarily the Rail Industry.  This of course ignores the directionally increased safety risks and petroleum consumption/carbon emissions, and the negative impacts on other commodities’ transport.  Making a final decision will, however, have other benefits such as stopping the waste of Canada’s focus on a possible future Keystone XL pipeline, so they can more fully focus on alternative pipelines needed to eventually get their Oil Sands into the Markets.

November 24, 2014    View Comment    

On Why Wind Farms Can Be Relied On For Almost Zero Power

Robert, your points on the impacts of variable, non-dispatchable wind power covers some of the obvious performance factors including the need for backup, fully dispatchable power (primarily natural gas and hydropower pumped storage under ideal conditions) and the primary benefit of reducing the fossil fuels consumption and associated carbon emissions from displaced baseload and intermediate coal/oil/natural gas capacity.  Another factor rarely highlighted is the fact that wind power capacity factors are most often ‘maximized’ by being given operating capacity priority over all other power generation sources (including hydro & nuclear in some cases).  The benefit of this operating practice is good for renewable power operators, but comes at a cost for consumers.  Besides the need for backup intermediate/peaking power capacity (often from fossil fuels), another less beneficial factor is the impact on fossil fuel power generation plant efficiencies; i.e. fuel consumption and carbon emissions per unit net power generation.  If wind power generation results in totally ‘shutting down’ equivalent amounts of average fossil fuels generation, the carbon emissions will be minimized and this benefit maximize.  However, all fossil fuel power plants have maximum designed efficiency levels of operation.  If the wind power merely reduces a natural gas power plant toward minimum rates (i.e. towards hot spinning reserve operation with minimal net power generation), the plant’s thermal efficiencies can drop towards half of design maximums.  Under this condition fuel consumption per KWh increases proportionally and the claimed/estimated carbon reductions by the wind power generator can be inflated considerably.

November 17, 2014    View Comment    

On Why Does the U.S. Still Need So Much Fracking Oil?

Nathan, thanks for a very good reference.  Another factor that impacts standards of living or suburban living vs. urban living choices and associated use of increased levels of privately owned-operate lighter duty vehicles (that primarily consume petroleum) is most often ‘economic based’.  The EU has the largest GDP in the world today, but on a per capita basis the U.S. average incomes are about 1/3 greater than the EU and per capita GDP is also greater in the U.S.  This factor is one of the reasons why those who can afford to move to apparently the more attractive living conditions outside higher density Cities have done so since WWII.  This trend could change, but not until living conditions in larger Cities improve to levels similar to more suburban settings as you have highlighted.  During the transition that could take at least many decades, if indeed it ever materializes, the U.S. needs to substantially increase the use of cleaner/higher efficiency EV’s and (non-petroleum) alternative fueled vehicles to significantly reduce Transportation Sector petroleum consumption.

November 15, 2014    View Comment    

On Why Does the U.S. Still Need So Much Fracking Oil?

Nathan, I agree that the probability of changing the current U.S. standard-of-living or moving the vast majority of Residents into high density Cities and shutting down a large part of the country’s infrastructure and economy based on a very mobile populous is extremely small in the foreseeable future.  The near future or practical solutions will most likely be higher efficiency and alternative fueled vehicles, which will include large fleets of BEV’s or (battery) EV’s.  And yes, biofuels still require 50%+ fossil fuels to produce and are far more carbon intensive that EV’s charged from Nuclear and Renewable Power sources.  The major economic barrier to EV’s is still the need to develop reasonable cost, high energy density, and safe batteries that have VMT ranges of a couple 100 miles between rechargings.  As you have focused on ammonia over the years, I am closely following the development of new technologies such as lithium-vanadium batteries.  The ultimate solution to replacing large percentages of petroleum motor fuels could be some balanced combination of battery, fuel cell and ammonia ICE vehicles in the future.

November 15, 2014    View Comment    

On Why Does the U.S. Still Need So Much Fracking Oil?

Roger, Geoffrey, and Nathan,  Very good discussion and debate on the pros-and-cons of options to current petroleum fueled vehicles and public transportation options.  To substantially reduce U.S. and other Countries’ Transportation Sectors’ petroleum consumption overall will eventually need to address a given country’s Demo- and Geographic’s.  Those who live in high population density cities have less need for personal vehicle transportation as long as some form of needed public transportation is available.  The same applies to city-to-city travel; if buses and rail can provide needed-timely transport of each Resident and their belongings.  As Nathan points out the time commitment and convenience can be an issue for those who live in the suburbs and work or otherwise must access goods and/or services in the cities.  This problem grows considerably for more rural settings.

The EU has one very significant advantage over the U.S.; population density.  The U.S. has a population density about 1/3rd Europe (90 sq.miles per capita vs. 30 in the EU).  This factor has significantly affected the Countries’/Economies’ development and Transportation Sectors vehicle mix/fuels consumption over the past 50-100 years.  As a result the U.S. economy & populous relies much more on independent-private vehicles (that overwhelming use petroleum fuels) than in European countries.  The challenge will be to transition the U.S. to higher average population densities, with lower independent mobility needs, and, do so without seriously risking the economy.  

November 15, 2014    View Comment    

On Why Does the U.S. Still Need So Much Fracking Oil?

Rick, the US/China agreement to curb CO2 appears to be more political than value added.  China appears to only consider peaking their carbon emissions by 2030, while President Obama suggests reducing total US carbon emissions by up to 28% in 2025.  Based on my past analysis of world carbon emissions, China’s carbon emissions could increase to a level nearly equivalent to the total of all Developed Countries (including the US) by 2030.  Not a very impressive outcome, particularly if CO2 does turn out to be the major variable towards climate change.

Anyway, this TEC Post outlines how the U.S. could feasible achieve a 28% reduction in total carbon emissions (in combination to the EPA Power Sector reduced carbon and other existing Federal/State regulations).

November 13, 2014    View Comment    

On Why Does the U.S. Still Need So Much Fracking Oil?

Engr.-Poet, the technology gap in displacing gasoline powered equipment such as most existing snowblowers with alternative electric units is due to limited availability and very high costs.  Those snowblowers that need larger power packs (or batteries) as you suggest would increase the unit costs by many times current market prices based on the relatively high costs of currently available larger-capacity/portable batteries.  Hopefully, near future innovations will substantially increase energy densities of available equipment (and EV) batteries and keep the cost to a small fraction of the total equipment/unit cost.  One promising developing technology is new lithium-vanadium batteries.  This developing battery technology could yield substantially higher energy densities, lower costs, and, be safer than currently available/state-of-art lithium batteries due to lower risk of overheating and fires.

November 13, 2014    View Comment    

On Why Does the U.S. Still Need So Much Fracking Oil?

Agreed, that’s why we need the Government to strongly support R&D in these and other promising areas.  And, get the Government out of the Commercialization or financially supporting  Industrial scale projects (project capital funding subsidies, loan guarantees, etc.).

November 12, 2014    View Comment    

On Why Does the U.S. Still Need So Much Fracking Oil?

Your idea sounds interesting if you can indeed get most commuters to routinely share rides all the time.  The alternative is of course Public transportation.

The estimated time required to convert most the existing U.S. vehicle fleet (or 150 million) will start with how long will it take to get the couple dozen driverless/computer controlled vehicles currently being build and tested, increased up to 15 million per year?  

November 12, 2014    View Comment