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From the simulations website:

"A megawatt-hour of electricity is about the amount a household uses in a month."

That is the elephant in the room. Our household of three adults can comfortably live on about one sixth of that amount.

Who can tell me with a straight face that living comfortably on three times our electricity consumption is impossible, even in a harsher, less moderate climate? That alone would reduce US household consumption by 50%!

I applaud Google for coming up with this tool. I also hope it will open its eyes to the feasibility of changing people's consumption patterns.



The elephant in the next room however is the couple of billion people who are pining for a sliver of the middle class (read: high energy) lifestyle we've taken for granted for close to a century. It would be grossly immoral to deny this lifestyle to them (never mind geopolitically impossible).

Sure, they get to skip a few steps on the ladder, and start out with LED lights and cheap insulation materials etc, but an energy efficient dish washer is more expensive than a less efficient one, and a well-insulated house is more expensive than one less so.

Yes, we should keep demanding better and more efficient solutions, to make sure they get developed, but the only responsible thing to do is to prepare for a future where global energy consumption is going up by quite a bit.


And the elephant in the third room is electromobility.

1MWh charges a Tesla Model S with a 100kWh battery 10 times, giving you 5400km of range.

If two people in a household are commuting 135km/day each for 20 days/month in a Tesla Model S, electrical energy consumption of the household doubles.


That elephant is not in the room yet. It's waiting at the Supercharger station a couple hours out on the highway, and won't be here for a quite some time. While that's changing with the Model 3 and the responses of other auto manufacturers, few people own or can afford a Tesla Model S. The elephant that's currently in the room is gasoline-based mobility.

5400 km in a gasoline-powered vehicle at 20 mpg or 14 liters per 100 km is 756 liters or 167.8 gallons of gasoline, and at 33.7 kWh per gallon, that's 5.655 MWh.

The commutes multiply the energy consumption by more than a factor of 5. You shouldn't feel good about turning off an LED bulb and using a lamp instead if you also enjoy driving to work in your pickup truck.


"If two people in a household are commuting 135km/day each for 20 days/month in a Tesla Model S, electrical energy consumption of the household doubles."

This is a big problem if everybody wants to charge at peak times. But most people charge overnight. Smart chargers and smart grids will ensure that loads get balanced and there isn't a huge spike in demand at 7PM when everyone plugs in as they get home from work.

In a future where grids are supplied largely by renewables and nuclear, EVs will benefit the grid by soaking up excess supply at off-peak times. When they're plugged in, they're effectively storage batteries on wheels.


absolutely this! IMO the energy conservation and carbon cost of electricity philosophy focuses attention on the wrong problem. The right problem to solve is how to generate more energy cheaper and with less harm to climate.

When I was growing up, we had neither heating, nor cooling. Summer temperatures would hit 40 deg Celcius. Winter temperatures would hit 1 deg celcius. It was supremely uncomfortable for much of the year and an active distraction against achievement.

Now I am well off and lead a comfortable life with climate control at my fingertips should I desire it. I would not willingly go back and definitely not have my child grow up that way.


There's one relatively simple method: if electricity cost more, it would be easy to justify investments in energy saving.

On the other hand, if the cost of things currently roughly depicts the environmental impact the things have, then it might not make sense to invest in energy saving with current technologies as that could have a very long payback time in environmental impact too.


I believe this is already the case in California. The most expensive energy by kWh but the lowest energy bills because of a statewide commitment to energy efficiency.

A carbon fee/tax/floor would be required to make things reflect their true cost in terms of climate change, this can be simulated in the app. Note that this isn't spending more money (at least up to the estimated social cost of carbon), since due to the externalities that cost is already being borne by sociery


Many Californians live in parts of the state where there is not much need for heating and cooling much of the year, which also helps keep consumption down.


A megawatt-hour is 1.38kW continuous consumption.

It's not hard to imagine how a household could use that. Two long how showers per day per person, air conditioning / heating, a pool heater, a fridge, another fridge in the garage, a deep freezer in the back room. Some people have multiple always-on PCs and screens.

And now we're expecting everyone to recharge their car at home too.


It's not difficult to imagine how a US household could use a MWh of electricity per month indeed. We know these are the facts.

Point is, it is possible to change those consumption patterns. Quoting from your example:

* heating: 67°F should be fine in winter. replace by natural gas where possible. invest in appropriate insulation and ventilation. Look at how much of northern Europe does it.

* air conditioning: use less and more recent airco. 76-77°F should be fine in summer.

* pool heater? just switch it off, or at the very least switch to a more efficient source of heating

* cut the second fridge in the garage, or at the very least, replace it with something efficient

* use an efficient freezer

* Check what machines have to be always on. Use something efficient for the things that really have to be always on.

I'm quite sure something along these lines would have cut more than 2/3 of the electricity consumption of this average American household.

It is physically possible to make these changes. I concede that it would not be easy to convince the people to actually make changes in this direction, but it can be done!


"heating: 67°F should be fine in winter. replace by natural gas where possible."

Replacing electric heating with natural gas isn't really valid as a long-term carbon solution. Certainly it's more efficient than using electricity produced from fossil sources, but it won't benefit from future grid improvements/decarbonisation. Heat pumps can deliver efficiency/cost comparable to gas in many countries.

Natural Gas heating is very common in the UK, but we're going to have to get rid of it eventually to meet climate goals.

The very low cost of gas also encourages people to burn more of it and overheat their homes (not uncommon to see flats with the boiler running and the windows simultaneously open for ventilation!). If we were thinking long-term, as you said, we're better off investing in better insulation and ventilation (MVHR).


> * pool heater?

This has to be the biggest offender of all the mentioned items.

The lower bound of heat required to raise the temperature of a 10mx6mx2m pool by 5 degrees Celsius is 700kWh, that's over 200kWh in electricity using a heat pump.


Yeah, my Dad has an outdoor pool with a heat pump, and the electricity bills are eye-watering. Thankfully he's now seriously looking at installing solar PV.


>solar PV

Fyi solar pool heating is a much cheaper option. They sell inexpensive unglazed plastic collectors specifically for this purpose. Reducing or eliminating that pool heating load should dramatically cut the PV system cost.

http://www.builditsolar.com/Projects/PoolHeating/pool_heatin...


Yeah, the pool actually did have this type of solar thermal heating originally, when they first bought the house around 15 years ago. But it wasn't very effective at heating outside of the peak summer months. Installing the heat pump meant they could swim around 5-6 months of the year instead of 2-3.

But to be fair, the collectors probably weren't big enough for the size of the pool. And the technology has probably also improved a lot since then - it was a pretty ancient set up.

PV is certainly more expensive but it has other utility besides just reducing the pool heating costs, as it will be able to generate reasonable energy year round for them (at ~45 deg latitude). If they didn't already have the heat pump then thermal might make more sense!


Or don't use AC altogether. Continuous AC always all-the-time is a very American thing.


I'd rather give up meat than AC, and I'm a meat lover. But I'm in the deep south, sure I'd give up AC in CO.


Makes sense for the South in summer months, sure. But in the USA as a whole, AC is used and abused even though there are solutions that involve building materials, behaviour and good habits that could make life livable. Temperatures get crazy high in Europe as well (40C or 105F is not uncommon in summer months in Spain or Italy and they do without AC). Using terra cotta, washing your floors, good use of shade, plants and trees, all that goes towards managing heat. Though the humidity in the southern US states does make it way more complicated, I'll give you that.


Not keeping shopping malls at freezing temps would help, too!


I used to think this until I spent some time in the tropics.

I folded u my temperate-climate clothes and put them away. They all went mouldy.

Although, I suppose that's just a knowledge / behavioural issue.


I propose a new type of economic system powered by crypto computing. A system where those that pay out the least in expenses get paid the most basic income. You could then normalize the distribution to avoid an inequality problem and overly harsh punishments.

You turn each BI account into a bank. So I can pay with my BI as a debt using an escrow account. The payee could then redeem the value for cold hard cash, or if they hold it and use it as money they get interest based on the value I continue to add to the account.

An expense is a payment using BI that is redeemed for value instead of held as currency.

This would encourage good savings patterns and also encourage lowering the potential debts that might become redeemed. This empowers the service providers to punish overusage of resources by redeeming values instead of holding them. You could also build into the contract an enforcement to just punish those that use the most resources by auto redeeming there values.

In the end these punishments don't kill people, but they should incentivise more humans to lower the amount of resources they use with that slight gamification.


The point is not that it's hard to imagine; it's that it can be considered normal. Why would people take two long showers every day?! Or leave screens turned on all night at home?


I gave up asking my partner to close the bathroom and bedroom doors when she is at home during the day with the heat pump set to 25 degrees C. It causes the heat pump to run flat out because it can't deal with that much hear loss.

And she's one of these save the whales type. And she wasn't working (receiving welfare) and I was paying the utility bills.

So I asked her to move out. Which doesn't solve the problem, just relocates it.

Point being, people don't know. And that's ok, there's plenty of stuff I don't know. We just need to engineer solutions to these problems. And maybe some of that is social engineering. But in the mean time: I give up.


spot on. But now, how do you make people accept the new normal in the (idealistic) time frame required by COP 21 goals ?


Pool heater? 3 fridges? The world wouldn't support this.


Does that include heating and hot water?

I consume ~8MWh/year in the UK. 1.5MWh of that is electricity, but the other 6.5MWh is gas mostly used in the winter months to keep warm. I set the temperature in my house to 17C (63F). I did go through a previous winter at 15C, but it just became too uncomfortable.


Another aspect of this is the fact many of those devices release a significant amount of radio frequency interference. Although mostly amateur radio operators and shortwave radio listeners are mostly affected that RFI does affect other electronics such as lights and TVs. Frankly, I wish the US govt would enforce its laws on energy efficiency and RFI more because they're not really that mutually exclusive barring switching power supplies (but even that to my knowledge is becoming less true as the regulator components are becoming even better at not producing as much RFI across the HF spectrum now).


People on youtube use fresnel lens as solar concentrator, you can get a lot of heat from this apparently (enough to melt just about everything).


What does your household do differently that allows your consumption to stay so low?


I'll guess : hang up clothes rather than put them in the dryer?


Not even close. An electric clothes dryer on an eco-friendly cycle typically uses about 1 kW. Older models on higher-heat cycles use up to a staggering...4 kW. And that's just for the few hours a month that it runs, it will be off for the other 720 hours.

The real difference is that OP probably lives in a well-insulated house in a moderate climate. In the hot, humid parts of the southern US, it's common to use 50 kWh/day just to keep the house liveable.


For clothes, we both hang up and use an efficient condensating drier.

We live in a (renovated) townhouse/terraced house in a moderate climate indeed, with good insulation and ventilation.

Limited always-on electric components here: fridge/freezer, internet modem, phone base station and ventilation system. No big screens. Cooking is electric though.


"Few hours a month" !! Ours runs for many hours every day.




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