Berkeley CSUA MOTD:Entry 44738
Berkeley CSUA MOTD
2018/07/22 [General] UID:1000 Activity:popular

2006/10/9-10 [Science/Electric, Science/GlobalWarming] UID:44738 Activity:high
10/9    So this whole plugin hybrid campaign thing...  Wouldn't that completely
        fuck the CA power grid if even a few % of drivers bought those?
        \_ the real issue is not rather CA power grid can handel it.
           I was told that if we modify it to make it plugin, it will
           drastically reduce the life span of the rechargable battery of those
           Prius, thus make the car a lot more prohibitive than it would
        \_ Electric power means "pollute elsewhere." The only way to reduce
           pollution is nuclear-- which will decimate population and reduce
           consumption, period.
           \_ Not necessarily.  A large power plant can run cleaner than a
              bunch of little power plants.  And nuclear seems to work in
              \_ no it doesn't.  French are racist and they have no problem
                 dumping nuclear waste in some French colony in the Southern
                 Pacific and completely disregards of people live there.
                 Unless we decided that it is ok to mimic what French does
                 in our Indian Reservation, the it is unlikely to work.
                 \_ Those aren't "our" reservations.  They are sovereign states
                    that you would have to buy the right from to dump on.
                    They are not colonies.
           \_ You're also forgetting the fact that "well to wheel", electric
              vehicles are far more efficient than the most efficient gas
              powered vehicles (including hybrids).
        \_ Probably not.  We can assume most people would plugin their car
           at night, which wouldn't have high electric  utilization
        \_ Yes, the power grid has no ability to power a significant number
           of electric cars right now.  -tom
           \_ Thanks tom!  I guess we're fucked... If only there were some sort
              of efficient human powered form of transportation... Nah, now I'm
              just being stupid.
           \_ Really?  I just did a "back of napkin" calculation.  CA ISO
              was providing 50,000 MW of power during the hottest summer
              day.  At night, the usage is typically half of that (or
              less).  Let's assume we have at least 15k MW spare capacity.
              I just checked the experimental plugin Prius.  They have
              the battery at 9kWhr.  Let's assume we can charge it (at
              night) 1kW for 9 hours.  This means the spare power capacity
              can potentially charge 15 million plugin prius.  I wouldn't
              call that insignificant.  Of course my calculation could
              be off by a power of 10 (or more).
              \_ We don't produce the same power off-peak; the only way
                 we could would be to burn more natural gas.  -tom
                 \_ Not disagreeing with you on this.  My point is that
                    a lot of the infrastructure is there for providing
                    "peak" power.  Why not use the capacity for off-peak.
                    Of course we'll burn more natural gas, coal,
                    whatever.  Energy is not free.
              \_ I think the infrastructure problem occurs more when a ton of
                 people plug in their cars when they get home at 6pm on a
                 scorching summer day or worse yet, while at work in the middle
                 of the afternoon.
                 \_ Well, yeah, the problem is that if we suddendly were
                    deriving, say, 5% of the power used by autos during
                    commute hours off the grid, we wouldn't have nearly
                    the capacity.  1 horsepower = 745 watts; do the math.  -tom
                    \_ Here's the math.  Say during one full day's driving,
                       your car needs to output the equivalent of 200hp lasting
                       10min (very unlikely) and not re-capturing any of this
                       10min (very unlikely) and not re-capture any of this
                       via re-generative brakes.  That's 33.3hp-hr.  Say you
                       charge your car between 10pm-8am.  Then the charger
                       needs to provide power at 3.33hp.  That's 2485.7W,
                       which is about the same as two hair driers.  Of course,
                       since neither charging nor motor-driving are 100%
                       efficient, in reality you need more than two hair
                       driers' power to provide 200hp-10min's of driving.
        \_ (
           "There is a synergy between increased use of PHEVs and expanded use
           of wind energy. Widespread use of PHEVs in an electric system makes
           it easier for that system to accept more wind energy. This is
           because most PHEVs will be charging at night, when demand for
           electricity is at its lowest, and wind energy production tends to be
           at its highest in many parts of the country. Also, PHEV batteries
           can act as storage for wind energy produced at off-peak times."
           \_ This would make sense if there was a switch on your car charger
              to only charge your car if the wind is blowing. Otherwise,
              they're firing up those polluting, expensive backups to
              charge your car when you ain't a blowin' in da wind.
              \_ Those polluting expensive backups are still usually cleaner
                 than car engines.  See the FAQ at the link above.
           \_ plug-in hybrid makes a lot more sense when combined with
              a charger system that has a timer to control when it charges,
              and time-of-use metering at the home to encourage users to set
              the system to charge on off-peak hours.  The off-peak power is
              cheaper to generate and tends to use large power plants that
              produce more efficiently but respond slowly to power demand
              changes, such as hydro and nuclear.  The peaker plants that run
              at peak hours usually are burning more expensive natural gas.
              \_ A timer for an AC outlet is not that expensive.  I bought a
                 mechanical 15amp one at IKEA for $8.
2018/07/22 [General] UID:1000 Activity:popular

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How much more will I pay for a PHEV, versus a comparably-sized conventional hybrid? There are prototypes in operation today, but there are no commercially available PHEVs on the market. DaimlerChrysler has developed and is testing a plug-in Sprinter Van prototype with an all-electric range of 20 miles. There are also many conventional hybrids, from sedans to SUVs, that have been converted to plug-ins. Some are getting up to 60 all-electric miles per charge. EnergyCS, replaced the standard 13 kWh battery pack with a 9 kWh battery pack. The larger battery pack was sufficient to provide half of the power needed to drive the first 60 miles each day. It's like having a second small fuel tank, only you fill this one with electricity at an equivalent cost of under $1 per gallon, depending on your car and your electric rate. You refill at home, from an ordinary 120-volt socket, with energy that's much cleaner and cheaper and not imported. The cost of the batteries needed to power a PHEV a sufficient distance is considered to be the stumbling block. However, battery technology is advancing rapidly and cost is expected to decrease with mass manufacture. What distance must a commercially produced PHEV be able to achieve on the battery alone? According to EPRI (Electric Power Research Institute), half the cars on US roads are driven 25 miles a day or less. Consequently, a plug-in with a 25-mile all electric range could eliminate gasoline use in the daily commute of tens of millions of Americans. Furthermore drivers of PHEVs would only need to fill up with fuel a few times a year, versus the current 24-36 times a year on average. Won't PHEVs just replace air pollution from automobiles with air pollution from power plants? In almost every conceivable power generation mix plug-ins reduce greenhouse gases and other pollutants. Additionally, emissions would be concentrated in one location that is often away from critically-endangered air sheds. Also, it is less difficult to control emissions from a relatively few number of smokestacks rather than millions of vehicle tail pipes. And, efforts to clean up coal plants and other emissions will continue. In recent decades, many power plants have been modified to lower emissions while a number of older plants have been retired. This trend has resulted in a 25% decrease in emissions from US power plants over the last 25 years. This trend is continuing so emissions will continue to get cleaner over time, meaning emissions generated from electric transportation will get cleaner over time. Furthermore, an increasing share of America's electricity is being produced by zero emission sources - wind and solar. There is a synergy between increased use of PHEVs and expanded use of wind energy. Widespread use of PHEVs in an electric system makes it easier for that system to accept more wind energy. This is because most PHEVs will be charging at night, when demand for electricity is at its lowest, and wind energy production tends to be at its highest in many parts of the country. Also, PHEV batteries can act as storage for wind energy produced at off-peak times. A Toyota Prius, modified with a larger plug-in battery, has essentially the same accelerating power and speed capability of a current hybrid. How much more will a PHEV cost versus a comparably sized conventional hybrid? The Electric Power Research Institute (EPRI) estimates that, with mass production, the cost of a PHEV battery will add $2,000 to $3,000 to the cost of a conventional hybrid. EPRI studies project that after considering the lower costs of fuel and maintenance, a mass-produced PHEV should provide better overall economics than either a conventional hybrid or a conventional vehicle. Battery costs are the primary reason for this incremental cost, and battery prices are likely to fall with increased production. The cost difference can be offset by federal and state tax credits and rebates designed to reward consumers for producing lower emissions and decreasing their consumption of petroleum-based fuels. Today, hybrid electric vehicle owners qualify for a one-time $2,000 Clean-Fuel Vehicle Federal tax deduction.
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Plug-In Partners is a national grass-roots initiative to dem-onstrate to automakers that a market for flexible-fuel Plug-In Hybrid Electric Vehicles (PHEV) exists today.