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Comment Re:unsportsmanlike buttock comfort (Score 1) 120

:) To be honest I think that more than 2 wheel recumbents suck. E.g. trikes are not good for healthy people who can maintain balance; trikes are too clumsy. But something like a two-wheel "high racer" with short wheel base are fine for normal city use. Occasional curbs up to about 6 inches are not a problem. One can just ride on a small curb slowly in approximately perpendicular direction without an issue. I use my recumbent for any errands which are over paved roads, do not need a car trunk and are not longer than 34 miles.

Recumbents are a complete crap outside of paved roads. You cannot do a bunny hop on them which more or less prohibits their use for "cross country", "trail", "enduro", ... Bumps are much more uncomfortable when your whole back is in contact with the bicycle (in contrast to just the butt). One cannot stand on pedals to overcome a bumpy region more comfortably.

Comment Re:How much difference does it make? (Score 1) 120

For Lithium Ion it is about 0.3 watts per gram. In other words, motor weight is a rounding error for battery weight. Well high power density motors are also high speed. They will need transmission with a big down-step ratio (somewhere in the range of 100). That will not be efficient (somewhere in the range of 50%). Other option is less energy dense, higher torque, lower RPM motor. Common electric bicycles use this approach to keep the whole electric support efficient since the battery capacity (energy density) is the biggest problem. Even bigger than battery power density.

Comment Re:How much difference does it make? (Score 1) 120

You can get small electrical motors in the power density range of about 8 watts per gram very easily. Just look for RC model motors. Long term power output of a competitive cyclist in a race is around 400-480W. You can double rider's power with only 60 gram motor. The battery is the harder part. The peak power output of a competitive cyclist is a bout 2 kW (time limited to a few seconds only).

Comment Re:Benefits to us All (Score 1) 120

I'd write the rules to say that the bicycle has to meet certain requirements for mass and volume, but beyond that anything is fair game.

It would transom cycling into a competition of small motorcycles. The limit should be: It must be only human powered and any stored energy in the bicycle should be zero joules at the start of the competition.

Comment Re:unsportsmanlike buttock comfort (Score 1) 120

... and driving the technology forward is an important part of most bike racing.

If that would be the goal then there would not be any technological limits except that it must be human powered and some basic safety limits (like it must have working brakes, ...).
No, bicycle races are not about technology. It is about marketing UCI approved bicycles to the masses

Comment Re:Morbo Voice: (Score 3, Informative) 190

French Energy Minister Agnes Pannier-Runacher countered that large-scale air conditioning would heat streets with exhaust, worsening heat waves.

"HEAT FLOW DOES NOT WORK THAT WAY!"

(For anyone who's unclear: all the heat that you're pumping out of houses is basically perfectly offbalanced by the heat penetrating into them.

It does work that way. Even if the AC would have infinite efficiency (instead of typical values of 2-3), you are increasing temperature out-of-the-house by reducing temperature in-house. But I agree in general that most of the time it will not matter and Agnes is wrong in practice. The reason being that the heat capacity of all the in-house areas is too small compared to heat capacity of all the outside areas. Therefore outside temperature increase will be negligible almost always. Maybe something will be measurable in narrow streets where air flow is low and which are full of AC radiators from the apartments around.

Comment Re:Inevitable? (Score 1) 203

The second chart I posted is about prices for companies - it is not that much different.

Something is very wrong with the EU electricity market when wholesale prices dropped by 64% based on ACER's "Market Monitoring Report" but end prices for companies dropped only by 14% and they stayed about the same for homeowners based on Eurostat.

Promoting market efficiency is rather strange when there is such a huge discrepancy between ACER's and Eurostat's claim. Something is very wrong with this allegedly "efficient" market or one of those two organizations is cheating. And if there is some cheating then I would bet it is ACER and not Eurostat.

My suspicion is that the "Market Monitoring Report" is cherry picking data to promote ACER's agenda and hide the real situation. If the common electricity would be abandoned then the burecrats in ACER are out of work :)

Comment Re: Inevitable? (Score 1) 203

Spot wholesale prices are varying a lot depending on the region, time of day, weekday and whether it is spring/summer (when solar works great during day) or autumn/winter. Typically prices are zero on spring/summer weekends during daylight. Otherwise they oscillate mostly around 0.1 with rare peaks to around 0.5 Eur/kWh during spring/summer. autumn/winter is slightly worse.
For example see: https://app.electricitymaps.co...

Comment Re:Inevitable? (Score 1) 203

Average European prices have been at their lowest in 2024 since 2021, despite volatility.

Did you look at the charts I posted? They are published by Eurostat which is the authoritative source for EU. The charts clearly show your claim is not true for households and it might be true for companies if your "since 2021" actually means excluding 2021 (i.e. since 2022). If there are any price reductions then they are not propagated down to households and mostly not propagated down to companies.

You are twisting truth like you work for an electricity exchange house in Germany :)

Maybe the common EU electricity market will work well in the future but so far its track record is very poor. Currently, the electricity price is tightly related to fossil fuel price since the last fraction of generated electricity is from fossil fuels.

Comment Re:Inevitable? (Score 2) 203

Europe has been moving towards a common energy market since 2006, and currently most of Europe is integrated, and the transition to renewable energy is part of this. Impact assessments have shown various technical, economic and administrative benefits, resulting in significant cost reductions.

There were no electricity cost reductions in Europe in the past 16 years for households. There was a huge bump in price after COVID and when Russia invaded Ukraine. After that it somewhat stabilized but it is still up by about 64% in this period: https://ec.europa.eu/eurostat/...

There was a small price drop for electricity for companies in 2023. But it is not dropping any more either now. And overall electricity price for companies went up by about 90% in the last 16 years: https://ec.europa.eu/eurostat/...

I call bullshit on your claim that electricity prices in EU are going down.

Comment Re:Birds, schmirds (Score 1) 97

0.5 Hz is more like now a wind is blowing a bit and now it is not :)
Different studies probably focus on different frequencies. This was my source: https://www.nature.com/article...
I know people complain about the noise and I would not like it either. But I would not mind them if they were far enough so that the noise is below 10 dB. Which means at least 500 m away for 20-200 Hz range. More may be needed for lower frequencies as you indicated.

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