Agreed! At least, I have been able to persuade my wife to wash & dry clothes, whenever possible, between noon and 3 PM, when solar output is maximum. That way I have a cost savings of 11.5 cents/kwh, instead of selling surplus electricity back to Alabama Power at 3.5 cents/kwh.
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Powerwall - Numbers don't add up (for me at least)
- Thread starter dckiwi
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- Powerwall Tesla Energy
Right; and a complicating factor is the reality that energy prices do not reflect the cost of damage to the environment. It's hard to price that; but at some point we will need to consider the cost of drought-created wildfires (many raging as I write this), and damage to coastal properties due to rising ocean levels. Oh well, the politicians will be able to say, "All that's going to happen on somebody else's watch."Well to be honest she and everyone else are a bi-product of the electric utility and appliance industries touting you 'can have it your way' for the last 75 years until just recently. So it's to be expected.
general sweetness
Although the on/off isn't going to work that close to the ground with kids around.
SageBrush
REJECT Fascism
That is not conservation, it is cost savings.
I agree though that the approach is the same.
By the way, ::two thumbs up:: on the solar array !
SageBrush
REJECT Fascism
- We cook. In Abq it was electric, in CO the stove is run off NG. I did give thought to efficient cooking and for our Vege/Vegan diets I settled on primary use of a toaster oven, microwave, stove-top, and electric kettle for hot water. I invested in efficient pots and pans and a pressure cooker. If I still relied on electric for the stove-top I would buy an induction heater.
- Kids are out of the house
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mspohr
Well-Known Member
I've taken a slightly different approach. I have installed efficient bulbs and appliances but I am not a fanatic about reducing electric usage. I am installing electric heat (air and water) instead of gas and adding solar panels to power it.
I don't think we should suffer. As long as I can keep adding solar, I will keep using as much electricity as I want.
I don't think we should suffer. As long as I can keep adding solar, I will keep using as much electricity as I want.
SageBrush
REJECT Fascism
"suffering" is trumpian hyperbole. You would be hard pressed to know that I live any different than you if you came to visit unless you paid close attention. Waste is not a convenience, it is just laziness.
Yeah sagebrush has stripped everything out of life to get to a low energy costs, eating tofu and okara every day; to me that's a very interesting lifestyle but not for me. At least for me that would be a non starter; I don't derive pleasure in such an ascetic lifestyle. I like to cook, I enjoy eating, house has kids running amok. I enjoy supporting local farmers and I drive around to get good local foods. But obviously he enjoys it so that's cool. If you have kids running in and out, 4 computers on, 4 cell phones charging, fridge, in a humid temperate climate than you are going to use much much more energy. His prior home is in the high desert and being part of a culture getting water from the Juan Chama may be a bit of salve to the original poster, the OP is at least he's basically drinking from the Occoquan or the Potomac (his own families back yard) and Fairfax has done a good job of creating parks around streams to keep the local reservoirs drinkable. Not perfect...sure but he's not killing the Colorado (not saying sagebrush is killing the colorado just that towns in the high plains/desert/mnt/ S CA are doing so and if you live there...)
SageBrush
REJECT Fascism
You have got it wrong and backwards. We eat soy because we like it. If I didn't, I would find other planet friendly-er food I like. Like all the other food I eat. And no, don't ask. It is too long a list.
You are looking for an excuse to brand me an ascetic so that you can rationalize your current behavior, but it is simply not true. All I really do is make an effort to avoid waste and embrace efficiency.
SageBrush
REJECT Fascism
After giving this some thought, and due to your insightful posts, I've decided to come clean and admit the truth: I am an ascetic.
- While true that I live in a 3800 sft home, it is all show -- a mirage. My actual home is a 6x4x4, mud cave in a corner of a shell built out of discarded egg shells and painted to match my neighbors fancy houses.
- My Soy diet is from my garden, fertilized by my night soil and urine to save on plumbing. No Walmart for me!
- Fermented food relieves me of the necessity of a fridge.
- It may *appear* that I drive to work, but in actuality my Prius is ICE-less. I pedal the car to work. Walking would be easier, but to be American is to drive.
- Internet access is easy: I thumb Morse code on the clothes-line to my local library, and a fellow ascetic uses a local computer to type my posts.
- And while true that I watched the World Series on a 55 inch flat-screen, it was through a window at my neighbors.
So there you have it. And to really be honest, I used to consume 5,000 kWh a month of electricity when I lived like you. So my hat is off to you guy -- you must be really smart. Or something.
OP here.
Nothing against @SageBrush - getting your energy consumption that low is an incredible feat. It's also not practical in our situation (we have a pool, and we need AC during the summer).
However, I just finished an energy audit of the entire home and man was it an eye opener. During the hottest summer months, our pool pump consumed ~1,100 kWh, pushing our monthly usage to ~3,000 kWh! Right behind that was the AC, which consumed ~900 kWh.
We can do a lot better. First, I am having a variable speed pool pump installed, which should reduce pool pump electricity usage by anywhere from 50%-90%. The pool is less than a year old and I'm annoyed that my pool builder never even talked to me about single speed vs variable speed, but it's my fault for not being better informed.
I'm sure we can also do better on HVAC usage. We kept the house super cool this summer. I'm going to keep it at a slightly uncomfortable level next summer, and make sure the thermostat is programmed to shut it off when we're out of the house.
My new targets are:
Summer peak months: ~2,000 kWh
Winter months: ~1,000 kWh
That includes ~300 kWh to charge my Model S. Our other appliances (fridges, computers, TVs) account for another ~380 kWh, and lighting is another ~200 kWh (total swag based on 35 9w LEDs and some outdoor LED lighting).
I know that ~2,000 kWh is still twice the national average, but it's probably about as low as we can go with our current lifestyle and location. I'm looking at a 7kW solar array that should give me about ~600 kWh/month.
That would bring me down to using ~1,400 kWh from the grid during the summer and ~400 kWh during the winter. And 40% of that grid power is from nuclear here in Virginia, with the rest from coal and natural gas.
Getting there. Any other suggestions welcome!
Nothing against @SageBrush - getting your energy consumption that low is an incredible feat. It's also not practical in our situation (we have a pool, and we need AC during the summer).
However, I just finished an energy audit of the entire home and man was it an eye opener. During the hottest summer months, our pool pump consumed ~1,100 kWh, pushing our monthly usage to ~3,000 kWh! Right behind that was the AC, which consumed ~900 kWh.
We can do a lot better. First, I am having a variable speed pool pump installed, which should reduce pool pump electricity usage by anywhere from 50%-90%. The pool is less than a year old and I'm annoyed that my pool builder never even talked to me about single speed vs variable speed, but it's my fault for not being better informed.
I'm sure we can also do better on HVAC usage. We kept the house super cool this summer. I'm going to keep it at a slightly uncomfortable level next summer, and make sure the thermostat is programmed to shut it off when we're out of the house.
My new targets are:
Summer peak months: ~2,000 kWh
Winter months: ~1,000 kWh
That includes ~300 kWh to charge my Model S. Our other appliances (fridges, computers, TVs) account for another ~380 kWh, and lighting is another ~200 kWh (total swag based on 35 9w LEDs and some outdoor LED lighting).
I know that ~2,000 kWh is still twice the national average, but it's probably about as low as we can go with our current lifestyle and location. I'm looking at a 7kW solar array that should give me about ~600 kWh/month.
That would bring me down to using ~1,400 kWh from the grid during the summer and ~400 kWh during the winter. And 40% of that grid power is from nuclear here in Virginia, with the rest from coal and natural gas.
Getting there. Any other suggestions welcome!
SageBrush
REJECT Fascism
Nice !
When it comes time to replace them, I imagine you can do quite a bit better. An inventory with power draws may be informative, or did the audit provide that information ? I have a pretty good idea of efficient appliances if you would like to provide a list. The EPA is also a very good resource for efficient appliance shopping.
I don't know anything about your locale or the specific shading problems you may have but 7200 kWh annual from a 7 kW array sounds quite low. I am under the impression 1.4 - 1.6 kWh per watt*year is typical US, while sunny places like my home in SW Colorado can collect 2 kWh per watt*year if a pole mounted array and seasonal tilting is used.
Actually I did the 'audit' myself, using a power usage plug (except my HVAC, which tracks energy usage itself). You're right that the age of the appliance makes a difference. I actually have three refrigerators (I know, I know. But you can pry my kegerator from my cold, dead hands!).
The main fridge in the kitchen is about 7 years old and uses 66 kWh.
The full size fridge in the bar is 2 years old and uses 31 kWh.
The kegerator uses 10 kWh.
My oldest TV is also an energy hog - a 13 year old 46" LCD that (with the amp) draws 285 watts.
I just took another look at my estimate. It's actually a 6.38kW system, with projected annual production of 7,351kWh. I have a very difficult roof (lots of angles) on which they say they can fit 22 SolarWorld 290 Watt panels.
Maybe I should shop around. Or maybe they're giving me a pessimistic power generation estimate.
Unrelated question - does the 900 kWh for the HVAC sound high? It's a two-zone system (each 3 ton units). I'm wondering if it's worth getting an efficiency assessment (insulation, doors and windows, etc.).
SageBrush
REJECT Fascism
Sorry -- I don't know. You could start by checking the SEER rating of the AC unit. But a good efficiency audit is a smart idea. A tight house could make an energy recovery ventilator (ERV) an efficient way to handle you local humidity and off-load your AC unit. If your domestic hot water is electric then consider a heat pump. If you can locate the pump in the home (noise considerations and availability of a drain apply), you will cool the home down and dehumidify for for free (energy and money wise) while heating water. Specific to hot water (particularly if it is electric), if you use a lot of water that drains through vertical pipes that are accessible, look into installing a drain water heat recovery pipe.
You may wish to contact @Topher through TMC. He is a home efficiency (and all-around energy) wizard and works in the field. Unfortunately he is probably too far away for you to hire, but he may have a referral for you and general advice.
From other internet stories, I gather that swapping out a pool pump is pretty expensive, and I honestly wonder if that is the best approach. How about just putting your pump on a timer for some daily filtering, and getting in the habit of turning it on when the pool is being used ? The general problem with non-variable pumps is that they do more work than is necessary -- they are over-spec'd for the job.
Are you familiar with PVwatts ? It is a brilliant web software for estimating PV production.
I don't deal with much AC up here, but for reference 6 tons of cooling, at 12,000 BTU/hour per ton, is 21,000 Watts (heat moved), at a SEER rating of (say) 14 equals 1.5kW (power used). For 900kWh per year gives 600 hours of operation. Does that sound reasonable to you?
At the risk of sounding self-serving, yes. Try to find an independent energy auditor, if you can, not one who is only interested on the work they can justify with the audit. I can't say anything sight-unseen, but I generally find that most homeowner's could save 50% of the energy bill through savings from fixes with less than a 7 year payback (aka worth-doing).
Possibly. Consult a local independent professional.
Thank you kindly
SageBrush
REJECT Fascism
Thanks for chiming in. Any advice how to find an excellent auditor ?
Also, I'd like to hear your opinion of variable speed pumps vs timed single speed in general and pump pools for dckiwi. I keep mulling over the possibility of installing an air-space heat pump for winter heating and this same choice (of variable vs single speed) comes up.
We have a 39k gal inground pool and are completely off grid. When we started building the house, many were eager to tell us that the pool wouldn't be supportable off grid. Being as we had already purchased the pool (it was a kit) before we moved, we choose not to listen. My solar guy suggested we get a DC pump to supplement the 240vac pumps that came with the system. A Speck pump and Lorentz PS600 controller. Don't know current cost, but if memory serves it was around $2k at the time. Initially we ran a dedicated 48vdc line from our solar system to the pump. Ran it on a timed schedule and according to sunshine or if the generator was running. Ran the 240 pumps to supplement on very sunny days or with the booster for the Polaris. Worked well, but something of a PITA as it was manually controlled and still a draw on the system, especially if I forgot to turn off until later in afternoon.
So a few years back, I made a change. Had 4 120watt Sharp panels that I removed from the Cottage when I combined systems. Remounted these panels at the pump house, wired in series for 48vdc and hooked directly into the Lorentz controller. Only change was a jumper so it knew it was direct PV and not battery. Disconnected my dedicated 48 vdc back to my system. So now, this one pump runs whenever the sun shines, speed varies with strength of the sun, but it does a fine job. I still run the 240s when I need a boost for cleaning. Works so well I added a solar heating loop.
So a few years back, I made a change. Had 4 120watt Sharp panels that I removed from the Cottage when I combined systems. Remounted these panels at the pump house, wired in series for 48vdc and hooked directly into the Lorentz controller. Only change was a jumper so it knew it was direct PV and not battery. Disconnected my dedicated 48 vdc back to my system. So now, this one pump runs whenever the sun shines, speed varies with strength of the sun, but it does a fine job. I still run the 240s when I need a boost for cleaning. Works so well I added a solar heating loop.
SageBrush
REJECT Fascism
Nice!
Presuming that you collect about 2 kWh per watt*year DC, the solar cleaning is consuming about 4*120*2 = 960 kWh a year, not including your AC supplement. That sounds like a pool I could enjoy.
