I have a modern cold climate air source heat pump which essentially needs to run 24 hours a day to maintain a stable 20C when the outdoor temperatures reach -15C. Below that, the heat pump shuts off and the furnace kicks in to provide emergency heating. My thermostat is a modern one with full time-of-day and day-of-week scheduling for heating and cooling, but it doesn't matter because the heat pump by itself is not able to swing the temperature up (by even half a degree) on its own, so this causes the furnace to kick in every time the schedule calls for a higher temperature, defeating the entire purpose of time-of-day scheduling.
I will also add that where I live (Southern Ontario) the sky is overcast 90% of the time during the winter. Solar panels, even somehow free of snow and ice, are going to produce almost nothing on those dark days. Add in the need to keep the panels free of snow and ice (presumably with heating, since nobody is going to be climbing around on their roof in the winter), and you'd likely reach energy net-negative trying to make use of them.
I also agree that 66F (about 19 degrees Celsius) is not comfortable during day time. It is fine for sleeping temperature. During winter homes in heating dominated climates typically have higher indoor temperatures. One advantage of lower inside temperature is that relative humidity stays slightly higher when it is very cold outside.
I've lived in extremely cold and extremely hot/humid places.
I cannot imagine setting the temp in the house that high.
At 66 degrees F? That sounds like put a sweater on if you’re chilly, not some near death extreme.
Any evidence that such an ‘extreme’ would cause issues?
Yeah, I understand I'm probably an outlier at 66F. I was using the numbers more to point out how little a house temperature will drop with good windows and insulation.
My house was built in the late 1980s. It has decent insulation but not amazing. It still needs a lot of heating when temperatures plunge below -15C. I do not have a whole-house humidifier. I had one with my previous furnace but it had issues with mold in the filter and clogging of the condensate pump.
I know people who live in the Mediterranean and get by with no heating during the winter with indoor and outdoor tempuratures this low or lower, so it seems that one can be conditioned into doing so.
Perhaps it's the presence of more sunlight on average rather than the temperature that makes the difference.
Thermal curtains are more effective than good windows. Good windows are minimally helpful.
In my last house, I replaced single pane windows with properly installed, sealed, and insulated double-hungs and it practically cut my heat bill in half. I agree that modern window to modern window replacement probably won't get you much, though.
If no one needs it during the day, they can't sell it. That's not how markets work. Energy that is generated, needs to be consumed or else the grid breaks down. These two facts together mean, that the energy they sell is needed and used. Albeit they could generate and sell even more energy, if the energy could be stored or if the load could be shaped accordingly. The latter is a great way to lower energy costs.
Energy consumption during the night is low. So low, that night time electricity prices, which are lower than the daytime prices, are still a thing.
Heat pumps are an opportunity for load shaping. Buildings can be heated, when electricity is abundant and heated a few degree over the target temperature, if needed. The heat is stored inside the building and needs less heating during the night. That works quite well, especially here in Europe were buildings generally have good insulation and are made of brick, which can store a lot of heat.
I genuinely do not understand why people are so afraid of solar. It's baffling.
The problem with global ecological regulations is they never differentiate between countries on the equator or 30th parallel with countries around 60. They expect everyone to only run on sun and wind. It isn't possible. There has to be at least nuclear which is ridiculously expensive.
It's generally not an easy problem to solve otherwise it wouldn't be a problem anymore.
First sensible thing to do is to relax the expectations for countries like Poland that have no good way to compete with other countries energy wise because of geographical location that noone chooses.
It is extremely unfair to treat everyone the same even though every country has different energy resources.
Yes surely some days are cloudy
So some days you get 5% capacity factor, and need some other energy source as well
So it harms the economics of the venture
Look at the profitability of companies building utility scale solar farms, they cost 100 million and the company hopes to get a 10% return and pay a 3% dividend.
They still have to contend with moving parts for tracking the angle of the sun, fans on inverters, contactors, clearing snow, mowing grass, site drainage, tornadoes etc, so sometimes it is not as easy as it sounds
All for a 7%? Why shouldn’t they just buy the s&p 500 and call it a day
But to be clear, it's less about night vs day and more about summer vs winter.
I had a 20kWh array and 18kWh of batteries in Texas and it was GREAT in the summer. It'd start charging by 6am and be charged by 9am, even with simultaneous usage. Then we'd live off solar for the day (even with HVAC), go back on batteries around 9pm and they'd be out around 4am. No problem.
But during an overcast winter day, the stack wouldn't get power until 8/9, not make it to 50%, start discharging by 4/5pm, and be out by 10/11pm. It would easily be 8-10 hours where we were wholly dependent on the grid.
Not a problem, just a constraint to acknowledge and plan for.