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On Self-Driving Car Technology's Benefits, Potential Risks, and Solutions

Nathan, the decision to make space flight primarily computer controlled was probably fairly difficult; particularly since it was made during the early development of autonomous control technologies.  But, as I recall a backup pilot was still required to take over control of the rocket/shuttle should a problem develop.  Even today there is still strong debate over the automatic piloting of commercial aircraft, particularly in landing in heavy fog conditions.  Despite many advancements over the years, all airlines still require pilots/copilots to operate safely under all conditions.

Yes, to avoid liability risks having some type of legal cover such as government certification is definitely ideal.  The certification process may be costly and time consuming, but the reduced liability risk is likely well worth the upfront expense.

Today the most common technology used to automatically control most cars is ‘cruise control’.  The driver does not have to constantly monitor the vehicle’s speed and only has to focus on keeping the vehicle safely within the lane of travel.  An autonomous ‘lane driving’ system is also under development currently.  In both cases the driver must still continuously watch the road for conditions and potential hazards that require taking over control and shutdown the auto-control systems.  ‘Breaking’ in the case of cruise control and ‘manually holding/turning the steering’ in the case of auto lane control is required as needed to continuously maintain safe operation while the vehicle is in motion.  Similar autonomous control switch-to-manual (after a beeper or other alarms) including manual breaking and/or steering or hitting a manual operation switch, will likely be included in self-driving/autonomous car controls until adequate upgrades and innovations make a truly ‘driverless’ car a safe and commercially available reality.

Agreed, having dedicated ‘computer (controlled) only’ lanes for physically separating future driverless cars from manually operated vehicles should greatly increase the safe and practical application/compatibility of future autonomous cars.

August 21, 2014    View Comment    

On Reality Check: Germany Does Not Get Half of its Energy from Solar Panels

Robert, very informative post on the ‘variable’ reality of solar PV power generation.  It’s very important that we continue to help educate the Publics on the pros & cons of variable-renewable power generation whose performance is largely conditional on weather conditions for a given day.  The problem most people have in understanding this factor is that most of us from Developed Countries have generally become spoiled over the years having grown up with ‘uninterruptable’ or on-demand and reliable power supplies.  Due to the normally reliable performance of most Developed Countries’ power grids those who are not involved with the design/operation or have not reasonably researched how power grid’s supply-demand are actually controlled, can be unaware of the many variables the must be continuously monitored and managed.  This of course includes the complexities of variable solar PV power generation, as needed to properly maintain and ensure that power grid stabilities.  Keep up the good work.

August 18, 2014    View Comment    

On Advanced Energy Technology of the Week: Efficient Building Insulation

Installing increased R-value insulation is only part of the solution.  For the insulation to be fully effective it must be installed properly to avoid in-wall/ceiling gaps that can significantly compromise the efficiency of a given volume of insulation material.  Also, besides eliminating door/window air leaks the HVAC air ducting must also be properly sealed and insulated to avoid this loss of building thermal efficiency.  High efficiency HVAC appliances are the other obvious requirements for top-efficiency buildings.  The next maximizing building efficiency action is ‘behavioral’.  The Residents must learn to not over cool (summer) or over heat (winter) to avoid waste of energy, and should take full advantage of external air temperatures to heat the house during the day and cold the house during the night by efficient managing air exchange with the outside during a given 24 hour period.  Properly managing window blinds-radiant heat is also part of the efficient operation.

Based on my personal design and having built my private residence I found my utility costs are on average 30-50% less than most my neighbors (in AZ) due to proper insulation, efficient HVAC appliances, and properly managing room/area thermostats and external air exchange.

August 14, 2014    View Comment    

On What are the Capacity Factor Impacts on New Installed Renewable Power Generation Capacities?

Gentlemen, I think we are talking different perspectives here, which appears to be creating large confusion.  Baseload normally refers to generation capacity that is dispatched (scheduled) at constant rates for a given longer operating periods.  As you should be aware, baseload normally comes from coal, nuclear, hydro, geothermal, biomass and (highest efficiency CCGT) natural gas.  These technologies are normally designed to operate at constant rates for longer periods of time vs. intermediate, peaking and when available-variable wind/solar.  Baseload power plants normally consist of numerous parallel/semi-independent power trains or units (boilers-steam turbines, reactors-steam turbines, gas turbines, etc. connected to individual generators) across a number of power plants.  Baseloads are maintained by operating each available and individual power train/unit (or sub-units for a given power plant consisting of many individual generation units).  The number of specific individual generation units in baseload service may vary daily, but the baseload generation net capacity is held relatively constant for the same demand periods each weekday or weekend period.  A given power plant with multiple generation units can provide the same level of baseload capacity 100% of the time for long periods; or until most or all the total plant must be shutdown for routine, major maintenance.

For any given future day you cannot schedule wind turbine power at specific baseload generation rates due to the variability of weather conditions.  Excess wind power must be exported (since operators want to always take full advantage of power generation tax credits vs. idling their production capacities) and power generation shortages (too low/too high of wind speeds) must be made up by dispatchable (on-demand/schedulable) intermediate/peaking sources such as natural gas and available hydro-storage in some cases.

August 8, 2014    View Comment    

On What are the Capacity Factor Impacts on New Installed Renewable Power Generation Capacities?

Advanced nuclear that is designed for intermediate (ramping up/down over relatively short time periods) service appears to be one issue you and I can possibly agree on.

August 8, 2014    View Comment    

On What are the Capacity Factor Impacts on New Installed Renewable Power Generation Capacities?

“Over 25% of the power generating capacity of wind could be used as baseload”.  This states that 25% of total power generation is essentially available from wind 100% of the time, 24 hours per day and every day of the year.  Unfortunately, nowhere in the world does the wind blow sustainably >50% of the time.  I agree that wind power should feasibly supply 25% of total power generation on average over a year; provided sufficient wind farms/capacities and transmission lines are available to shift wind power generation with changing wind patterns, and sufficient backup power (today normally natural gas) is available as needed.  But, to assume that 85% of baseload (of roughly half of daily average total-peak demand) can be reliably supplied by variable/unpredictable/un-dispatchable wind power risks routine brown-/black-outs in power grids/regions that lack sufficient backup/fully dispatchable (controllable 24/7) intermediate/peaking power.  Yes, intermediate power can be provided by our limited hydropower/pumped storage, but on average most of this on-demand/fully dispatchable power generation capacity is provided by natural gas.  This trend will likely continue well into the future until Industrial scale power storage (in addition the hydro) becomes a feasible, cost effective reality.

August 8, 2014    View Comment    

On What are the Capacity Factor Impacts on New Installed Renewable Power Generation Capacities?

Good point.  Geothermal power storage is probably best suited for developing Industrial scale batteries.

August 8, 2014    View Comment    

On What are the Capacity Factor Impacts on New Installed Renewable Power Generation Capacities?

Michael, my analysis addresses a specific FERC report recently highlighted by a number of organizations and individuals in general terms and some of the details you have highlighted that can further confuse the issue of renewable power operating penetration levels and impacts.  But for some further clarification of your comments:

1.      The listed capacity factors of table 2 for natural gas (refer to the table sub-note) are ‘design’ maximums for ‘baseload’ operation that would exist in displacing existing design baseload ‘coal’ power generation capacity.  Wind power unfortunately cannot provide or displace baseload power generation capacity due to its variable nature.  The baseload actual capacity factor is of course a function of how the power grid operator chooses to optimize their base (constant), intermediate, variable (wind) and peaking power loads as needed to reliably meet changing demand 24-7.  This balance is a somewhat complex optimization of daily demand curves, variable wind/solar supply, scheduled power generation maintenance (and startup of new power generation), variable demand (both controllable and uncontrollable), etc. 

As far as “new plant’s performance not varying from existing-older plants”, there is strong precedent that new plants will have significantly greater capacity factors (and thermal efficiencies).  A very common business practice for most (successful) Industries is to continuously improve the efficiencies, operating performance and reduce expenses.  How do you suppose that wind turbine technology has changed from past sub-MW, <30% capacity factors to state-of-art multi-MW >30% capacity factors over the years?  This practice is why natural gas average thermal efficiencies (Re. a past TEC Post, “Average Thermal Efficiency of US Net Power Generation” graph) have increased by almost 30% since the 1990’s.

2.      The FERC report was only based on the first halves of 2014/2013.  If FERC had recently reported on an annual basis we would be probably having a somewhat different debate/discussion.   Yes, wind power capacity has definitely been the largest growth in total U.S. generation capacity in recent years.  As you are very aware, the major expansion factor is due to States’ renewable power standards and the Fed’s 10-yr. production tax credit that expired last year, but still made those projects ‘under construction’ eligible for the 2.3 cent/KWh tax credit for up to 10 yrs.  Fortunate for your Industry the approved definition of ‘under construction’ appears to be somewhat liberal (it use to mean: “following the actual physical breaking of the ground for initiating construction”, but it appears to now include those projects just in the design phase).

3.      Agreed, we should save the ‘levelized cost’ discussion for a future discussion/post.

By the way, I am an advocate for wind power generation capacity needed to reduce future U.S. carbon emissions.  My major concern is and has always been the economics, overall balance and maintaining a reasonable level of power grid stability during short-term and long-term operations, and under all weather conditions.

August 8, 2014    View Comment    

On What are the Capacity Factor Impacts on New Installed Renewable Power Generation Capacities?

Peaking natural gas plants can possibly have capacity factors as low as 3% when on-line and operating at near minimum rates (or basically hot idling until ramping up power is required).  But on average I suspect most Power Companies operate their equipment a bit more efficiently (higher average capacity factors).  And yes, solar does generally overlap with daily peaking power, which of course is based on non-cloudy days.  When loss of (variable) solar PV generation occurs during the balance of peaking power periods this of course requires intermediate/peaking natural gas power plants to ramp-up generation; and increase their capacity factors.  This is a normal operating characteristic of ‘uninterruptable’ power supplies and grids we in the U.S. have grown accustom to over the years.

Yes, the EIA data on solar (Re. recent reporting) has been newly developing and is not fully accurate or likely complete at this time.  This inaccuracy is likely due to some combination of incomplete/developing data bases and possibly lack of consistent data (and not likely due primarily to politics).  The Feds generally don’t require detailed reporting of installed and actual generation capacities unless the data is required such as for ‘generation tax credits’ and other subsidies.  Individual State’s (CA, TX, etc.) are probably the most accurate sources of Residential/Commercial Sectors solar data and capacity factors at this time.

Achieving local/regional capacity factors >40-50% with variable wind & solar for ‘uninterruptable’ power supply and without storage or backup power generation is highly improbable.  That 50-60% of the time when the sun does not shine and/or the wind does not blow means the power supply will be ‘interrupted’ and the consumer must either obtain backup battery or generation power to meet their needs, or sit in the dark until weather/daily conditions change.

August 8, 2014    View Comment    

On What are the Capacity Factor Impacts on New Installed Renewable Power Generation Capacities?

Clayton, excellent data reference on the synergies between renewable power sources.  Thanks.

August 7, 2014    View Comment    

On What are the Capacity Factor Impacts on New Installed Renewable Power Generation Capacities?

Yes a typo, I obviously meant a half milllion.

August 7, 2014    View Comment    

On What are the Capacity Factor Impacts on New Installed Renewable Power Generation Capacities?

Another possible synergy or compliment to wind power capacity factors is solar PV.  Solar capacity factors overlap normal daily demand peaks (mid-afternoon) generally to a greater degree than wind power and wind power capacity factors are of course much greater after sunset.  As you state, the balancing of daily normal-peak demand is currently supplied by intermediate/peaking natural gas power.  Without Industrial scale power storage, various forms of demand response directionally help balance supply-demand.  But, this controllable demand needs to be expanded substantially to become a much more significant part of current power grid supply-demand operation balancing controls.

Other (non-storage) options to replacing the need for natural gas power are unfortunately fairly limited.  Non-hydro storage renewable options could include biogas and possibly geothermal (with energy storage similar to solar thermal), but these technology innovations are currently very slow in developing.  I my opinion (advanced/intermediate) nuclear has somewhat greater promise.  This technology unfortunately is not currently supported very strongly by State and Federal Governments.

August 6, 2014    View Comment