Windows are bad. Sure our lives would suck with out them but were trying to go green here...
But wait, if we have lots of glass and the associated natural light I can keep my lights turned off. Just think of the savings! Except at night, or when there are temperature differences outside etc. Oh well. never mind.
Windows are bad.
If you live in a new, well insulated house, your walls will probably have a high R-value. They will perform well right up to the window. And, in newer homes we insist on lots of natural light so they have lots of windows. In fact, even in my 1965 home I have walls that are way more glass than wall.
These designs grew out of cheap energy and a "don't care" attitude about pollution, climate change etc. It will be interesting to see how architecture changes as we become more sensitive to these issues.
Or maybe we can whip this with technology. Maybe we will get to where a window is as good as a wall. Of course it will cost you more than a small nuclear reactor, but it will be greener! Or we could wait around for solar panels that are reasonably priced to generate our energy so we don't care how much the windows lose. We're 30 years and counting so far.
When you're looking at making your home energy efficient, the windows are a primary concern, but they are also a big expense if you want to change them. Generally, it's really hard to cost justify window changes, but there is lots you can do in the mean time.
It's worth noting that a window, or maybe more accurately, a piece of glass that's built into your wall that doesn't open can be replaced much more cost effectively. In fact, in my home, it was cheaper than blinds. There is no frame, locks, mechanisms etc, it's just a glass sandwich. Costs for a triple pane low-e glass unit can be pretty reasonable, they usually install easy, and they make a big difference. And lastly they are eligible for tax credits if they are certified.
But, the easy thing to do on all windows is make sure they don't leak. Weather stripping and caulk are usually the answer. Next we need to just blanket the window. Heavy curtains, blinds etc all help a lot. One has to remember to use these items when there are considerable temperature differences from inside to out. You also don't want to have openings at the top and bottom of the coverings or you will have just built an air convection heating (or cooling) machine.
One can also install clear plastic (from 3-M) to the windows inside to build an air gap and seal the whole thing. These work reasonably well and make a huge difference, for just a little time and money.
Bottom Line - Standing in any room, your likely largest energy user is the window(s). They are worth the time to make them energy efficient and there are good price options from plastic all the way up to new windows (that should probably still have coverings).
Thursday, June 18, 2009
Sunday, June 14, 2009
How important is the attic to our heat and cooling bills?
I like this question, because it asks, why do I care, about something so tried and true.
If I stand in the middle of a room in my house, how much is ceiling? In a 12 x 12 room, the ceiling is 144 sq ft of area to be concerned about. If the ceiling is vaulted, it's even more.
In that room, each wall is 12 foot long, and let's say 9 feet tall. That wall is 108 square feet. If it's on the outside of the house we care, if it's on the inside, we don't. So how many walls are on the outside per room? In my house it's one or two per room typically. (Corner rooms are two.)
So if its one wall, it's 108 square feet -vs- 144 on the ceiling. If it's two, then its 216 vs 144 square feet of ceiling. No matter what, the ceiling is a big percentage of any room sitting under the attic.
Now, to be accurate, much of those exterior walls are penetrated by windows. Big chunks of square feet are actually glass. If you super insulated an exterior wall, but left a big single pane window in the middle of it...you will have missed the point.
But back to attics. In a single story home, all the rooms have ceilings touching the attic space. Simply put, a 3000 square foot home has about 3000 feet of ceiling touching the hot attic! A full two story would be about half that.
The most important reason to focus on attic is because we can actually do something about the problem pretty easily. Attics are accessible, the inside of your exterior walls aren't, (without serious deconstruction.) Blowing insulation, radiant barriers, and venting are all pretty easy, there are lots of contractors to choose from and it doesn't disrupt our lives...much.
Bottom Line - Attic is very important and easy to deal with.
If I stand in the middle of a room in my house, how much is ceiling? In a 12 x 12 room, the ceiling is 144 sq ft of area to be concerned about. If the ceiling is vaulted, it's even more.
In that room, each wall is 12 foot long, and let's say 9 feet tall. That wall is 108 square feet. If it's on the outside of the house we care, if it's on the inside, we don't. So how many walls are on the outside per room? In my house it's one or two per room typically. (Corner rooms are two.)
So if its one wall, it's 108 square feet -vs- 144 on the ceiling. If it's two, then its 216 vs 144 square feet of ceiling. No matter what, the ceiling is a big percentage of any room sitting under the attic.
Now, to be accurate, much of those exterior walls are penetrated by windows. Big chunks of square feet are actually glass. If you super insulated an exterior wall, but left a big single pane window in the middle of it...you will have missed the point.
But back to attics. In a single story home, all the rooms have ceilings touching the attic space. Simply put, a 3000 square foot home has about 3000 feet of ceiling touching the hot attic! A full two story would be about half that.
The most important reason to focus on attic is because we can actually do something about the problem pretty easily. Attics are accessible, the inside of your exterior walls aren't, (without serious deconstruction.) Blowing insulation, radiant barriers, and venting are all pretty easy, there are lots of contractors to choose from and it doesn't disrupt our lives...much.
Bottom Line - Attic is very important and easy to deal with.
Solar attic fans
There is a new product out on the market, well sorta new. It's the solar powered attic fan that sits on your roof and draws air out of your attic for free! Well, $600 free. This is a product who's time has come...to be left at the store where it belongs.
Many of us have the turbine fans that passively turn when we get a little breeze. They are cheap to buy and also free to run. There are also powered fans that have thermostats to turn them on and off depending on attic temperature. They require electricity to be run to them (and paid for). There are also ridge vents that run the entire length of the roof top and vent the attic passivly through convection.
Now the solar fan adds a fourth option. If you have read my previous post you may spot the problem with these fans. True they go in without an electrician and when the sun is shining and you are gaining heat in the attic, they work well. But what happens when the sun isn't shining?
First, as the sun is setting they begin to slow down because of the reduced light hitting the collector. The heat in the attic, from all the radiant heating of the stuff continues to build. As evening comes and the outdoor air cools, the fan stops, just when you need it to be pulling cool air into the attic and cooling all the stuff. So the insulation becomes saturated with heat as it sits all night baking with no cool air.
The next day, the process starts over again except the attic never cooled, so today's heat is added to what's left of yesterday's. The fan runs all day keeping up with the new heat, then shuts off again.
Bottom line - The attic needs venting 24 x 7 in the summer. Spending $600 apiece to vent only when the sun is shining on them, is very questionable.
Maybe there is some justification to adding one of these to an existing complete attic venting solution, I dont know. And for $600 plus installation, I doubt I will find out.
Many of us have the turbine fans that passively turn when we get a little breeze. They are cheap to buy and also free to run. There are also powered fans that have thermostats to turn them on and off depending on attic temperature. They require electricity to be run to them (and paid for). There are also ridge vents that run the entire length of the roof top and vent the attic passivly through convection.
Now the solar fan adds a fourth option. If you have read my previous post you may spot the problem with these fans. True they go in without an electrician and when the sun is shining and you are gaining heat in the attic, they work well. But what happens when the sun isn't shining?
First, as the sun is setting they begin to slow down because of the reduced light hitting the collector. The heat in the attic, from all the radiant heating of the stuff continues to build. As evening comes and the outdoor air cools, the fan stops, just when you need it to be pulling cool air into the attic and cooling all the stuff. So the insulation becomes saturated with heat as it sits all night baking with no cool air.
The next day, the process starts over again except the attic never cooled, so today's heat is added to what's left of yesterday's. The fan runs all day keeping up with the new heat, then shuts off again.
Bottom line - The attic needs venting 24 x 7 in the summer. Spending $600 apiece to vent only when the sun is shining on them, is very questionable.
Maybe there is some justification to adding one of these to an existing complete attic venting solution, I dont know. And for $600 plus installation, I doubt I will find out.
Friday, June 12, 2009
Attics. Advanced class in thermodynamics
Ya right, I don't even know what thermodynamics means. What I do know is heat transfer is what all this green home energy conservation stuff is all about. Trying to keep cool and warm where it belongs.
Thinking about it, your gas, oil, electricity use is all increased by various losses or waste of hotness or coolness. So what's important is how.
Heat transfers three ways, conductive, ie finger touches hot pan, convection, air above the pan rises and cooler air replaces it to be warmed etc..., and radiative...you feel the heat from the pan at a distance but the air in between is a normal temperature.
It's that last one that is really tricky. Hot surfaces "radiate" heat via invisible waves traveling at the speed of light. If you have ever sat under a restaurant heater you may have noticed it warmed you although the air was still cool. That's radiative heating. So why do we care?
Well all of those radiant barrier ads on the radio and in your mailbox are about stopping the radiative effect of the sun on your roof. They basically stop the radiating of the heat into the attic. They promise huge energy savings for us Texans. But before you run to the phone to get some...lets make sure we understand the challenge.
Your attic is full of stuff, not only your camping gear you never use but also the insulation, rafters, duct work etc. The radiative heat, heats all of this stuff, just like you at the restaurant.
The insulation has a couple of jobs. First it keeps convection from taking all the cool from your ceiling and sending it out the vents. It also slows the heat in the attic from soaking through your ceiling into your living space. (Conduction).
So the air is hot, and the stuff is hot, and as long as the sun is shining on the roof the more radiative and conductive heat will be transferred into your attic. A simple shade tree drastically reduces these two heating effects. But, for those of us in the sun, where we make a mistake is thinking that some air vents and insulation are all we need.
Radiant barrier basically reflects the invisible heat energy back. Then your attic is only heated by conduction and convection. Air moves in, comes in contact with the "under roof" surface that has been warmed by the sun, heats up and rises. This goes on all day and into the night. If you have enough insulation, that heat never really gets to your cool ceiling before it cools off for the night.
So, we could keep piling insulation up in the attic. The air above it and all the stuff would be super hot. That heat will slowly seep further and further into the insulation where it will reach the topside of your ceiling and begin to warm the air in the room. The more insulation I have the longer it will take to become saturated with heat and the slower the heat transfer will be. Or, we can vent the attic and take advantage of convection to keep removing the hot air and replacing it with cooler outdoor air. If we move enough air we can keep the attic reasonable in air temp.
Combine those two and you have a pretty good system for keeping a handle on conductive and convection heat, but we are still at the mercy of the radiant heat. Add the radiant barrier and you have really cooled your attic and given your insulation a chance to do its job.
Taking this a logical step further, there are new homes being constructed with the radiant barriers and insulation under the roof with a sealed up attic and no insulation between the attic and the living area. The idea is that the attic is kept cool by the transfer of heat through the ceiling and conditioning the air. For all of us, it doesn't make sense to do that on an existing home.
Bottom Line - Radiant heat needs to be addressed, especially if your duct work runs through that space. Insulation and venting are good, but not good enough to really make a difference in your cooling bill. But you also can't believe those claims of 30% savings. The pros will tell you its 8 -12%.
It's time to call some contractors and find out what this stuff costs...it's 95 degrees today. Using a simple ROI calculation of...what's the cost of the barrier vs saving 10% on my electricity bill in the summer months should be a good starting point. If that looks reasonable then we will do the harder calculation of 10% of just the air conditioning portion of the electric bill per month.
Thinking about it, your gas, oil, electricity use is all increased by various losses or waste of hotness or coolness. So what's important is how.
Heat transfers three ways, conductive, ie finger touches hot pan, convection, air above the pan rises and cooler air replaces it to be warmed etc..., and radiative...you feel the heat from the pan at a distance but the air in between is a normal temperature.
It's that last one that is really tricky. Hot surfaces "radiate" heat via invisible waves traveling at the speed of light. If you have ever sat under a restaurant heater you may have noticed it warmed you although the air was still cool. That's radiative heating. So why do we care?
Well all of those radiant barrier ads on the radio and in your mailbox are about stopping the radiative effect of the sun on your roof. They basically stop the radiating of the heat into the attic. They promise huge energy savings for us Texans. But before you run to the phone to get some...lets make sure we understand the challenge.
Your attic is full of stuff, not only your camping gear you never use but also the insulation, rafters, duct work etc. The radiative heat, heats all of this stuff, just like you at the restaurant.
The insulation has a couple of jobs. First it keeps convection from taking all the cool from your ceiling and sending it out the vents. It also slows the heat in the attic from soaking through your ceiling into your living space. (Conduction).
So the air is hot, and the stuff is hot, and as long as the sun is shining on the roof the more radiative and conductive heat will be transferred into your attic. A simple shade tree drastically reduces these two heating effects. But, for those of us in the sun, where we make a mistake is thinking that some air vents and insulation are all we need.
Radiant barrier basically reflects the invisible heat energy back. Then your attic is only heated by conduction and convection. Air moves in, comes in contact with the "under roof" surface that has been warmed by the sun, heats up and rises. This goes on all day and into the night. If you have enough insulation, that heat never really gets to your cool ceiling before it cools off for the night.
So, we could keep piling insulation up in the attic. The air above it and all the stuff would be super hot. That heat will slowly seep further and further into the insulation where it will reach the topside of your ceiling and begin to warm the air in the room. The more insulation I have the longer it will take to become saturated with heat and the slower the heat transfer will be. Or, we can vent the attic and take advantage of convection to keep removing the hot air and replacing it with cooler outdoor air. If we move enough air we can keep the attic reasonable in air temp.
Combine those two and you have a pretty good system for keeping a handle on conductive and convection heat, but we are still at the mercy of the radiant heat. Add the radiant barrier and you have really cooled your attic and given your insulation a chance to do its job.
Taking this a logical step further, there are new homes being constructed with the radiant barriers and insulation under the roof with a sealed up attic and no insulation between the attic and the living area. The idea is that the attic is kept cool by the transfer of heat through the ceiling and conditioning the air. For all of us, it doesn't make sense to do that on an existing home.
Bottom Line - Radiant heat needs to be addressed, especially if your duct work runs through that space. Insulation and venting are good, but not good enough to really make a difference in your cooling bill. But you also can't believe those claims of 30% savings. The pros will tell you its 8 -12%.
It's time to call some contractors and find out what this stuff costs...it's 95 degrees today. Using a simple ROI calculation of...what's the cost of the barrier vs saving 10% on my electricity bill in the summer months should be a good starting point. If that looks reasonable then we will do the harder calculation of 10% of just the air conditioning portion of the electric bill per month.
What's normal? Average?
In my quest to know where I stand, I have attempted to measure my sustained place in this world against others. What's my level of greeness? Am I good, bad, or even the dreaded "average"?
In fact, I started my work on sustainability with a trip to the Energy Star web site to measure my energy use against others in an attempt to see where I stand. As I blogged then, my house was a zero on a scale of zero to one hundred. That's pretty bad.
Reader Mathias sent a link for Wattzon, another site with a measuring tool against all others who have filled out the simple forms. They go a step further and try and convert everything to watts to allow us to compare apples to apples.
But I suggest the flaw in all of this is us measuring against the average. Not because it isn't fun, but because it isn't useful. In fact, I think measuring at all against each other is seriously wrong headed. (It smacks of my religion being better than yours, and we know where that ends up.)
As my brother-in-law says, half jokingly, it's a personal journey.
So how do we encourage ourselves on our personal sustainability journey? How do we know when we have accomplished something meaningful? Worthwhile to our planet, kids, grand kids etc? We should measure against ourselves.
Bottom Line #1 - We need to measure our journey's successes against our own pasts.
I believe in goals, but again, setting a goal against the average, or your neighbor, isn't relevant in my view. Set a goal to achieve a 30% reduction in all things related to sustainability, compared to yourself. Measure your starting point, and take out 30%.
I think you'll find that 30% is mostly waste, not use. That 30% is the way we did things out of habit or the way we were taught. That 30% is also things that are available today to help us get there with reasonable cost and payback.
Bottom Line #2 - We need to eliminate the waste, build new habits and put to use some new products or services to help us achieve 30%.
So you might encounter someone who brags about their footprint, their journey, their rain barrels. Have them tell you me how much they have reduced against their start of this journey. If they can, that person is trying to better themselves, not compete against someone else.
If you get a long story about the effort or money spent, or how cool their new Prius is, don't take it as a challenge, they are probably hiding a Hummer at the lake house.
In fact, I started my work on sustainability with a trip to the Energy Star web site to measure my energy use against others in an attempt to see where I stand. As I blogged then, my house was a zero on a scale of zero to one hundred. That's pretty bad.
Reader Mathias sent a link for Wattzon, another site with a measuring tool against all others who have filled out the simple forms. They go a step further and try and convert everything to watts to allow us to compare apples to apples.
But I suggest the flaw in all of this is us measuring against the average. Not because it isn't fun, but because it isn't useful. In fact, I think measuring at all against each other is seriously wrong headed. (It smacks of my religion being better than yours, and we know where that ends up.)
As my brother-in-law says, half jokingly, it's a personal journey.
So how do we encourage ourselves on our personal sustainability journey? How do we know when we have accomplished something meaningful? Worthwhile to our planet, kids, grand kids etc? We should measure against ourselves.
Bottom Line #1 - We need to measure our journey's successes against our own pasts.
I believe in goals, but again, setting a goal against the average, or your neighbor, isn't relevant in my view. Set a goal to achieve a 30% reduction in all things related to sustainability, compared to yourself. Measure your starting point, and take out 30%.
I think you'll find that 30% is mostly waste, not use. That 30% is the way we did things out of habit or the way we were taught. That 30% is also things that are available today to help us get there with reasonable cost and payback.
Bottom Line #2 - We need to eliminate the waste, build new habits and put to use some new products or services to help us achieve 30%.
So you might encounter someone who brags about their footprint, their journey, their rain barrels. Have them tell you me how much they have reduced against their start of this journey. If they can, that person is trying to better themselves, not compete against someone else.
If you get a long story about the effort or money spent, or how cool their new Prius is, don't take it as a challenge, they are probably hiding a Hummer at the lake house.
Wednesday, June 10, 2009
Xeriscape is now "Water Wise"
Due to everyones inability to wrap their head around the word "xeriscape" we are now calling these landscapes or plantings "Water Wise". Dallas just hosted their annual Water Wise home tour this last weekend and I went along for the ride.
First, there are still plenty of examples of what I now call the "English Garden" look. It's an eclectic mix of plants that smacks of way too many trips to the plant store. "Oh look, lets get one of those and see how it does."
There are also examples of Water Wise that clearly aren't. One had an artificial stream running through it! She said (since I asked) that her water bill is only $32. They must not shower in that house.
But I was heartened to see that some designers were beginning to grasp the idea without making a mess. I saw a one really nice example out of the 10 we visited, and the 10 that I viewed on-line. Unfortunately not one of the homeowners was touting a percentage of savings from the effort. I find that curious but maybe I am the only one who actually tracks the savings from my non "Water Wise" yard.
So, next year I plan on entering the event. I am going to show how to get 30% water savings and look like a normal landscape. Every time someone says "well where is the jumble of water wise plants"? I'll just turn the sprinklers on them.
First, there are still plenty of examples of what I now call the "English Garden" look. It's an eclectic mix of plants that smacks of way too many trips to the plant store. "Oh look, lets get one of those and see how it does."
There are also examples of Water Wise that clearly aren't. One had an artificial stream running through it! She said (since I asked) that her water bill is only $32. They must not shower in that house.
But I was heartened to see that some designers were beginning to grasp the idea without making a mess. I saw a one really nice example out of the 10 we visited, and the 10 that I viewed on-line. Unfortunately not one of the homeowners was touting a percentage of savings from the effort. I find that curious but maybe I am the only one who actually tracks the savings from my non "Water Wise" yard.
So, next year I plan on entering the event. I am going to show how to get 30% water savings and look like a normal landscape. Every time someone says "well where is the jumble of water wise plants"? I'll just turn the sprinklers on them.
Tuesday, June 9, 2009
Where have I been? Thinking of 30%
I have been spending an inordinate amount of time repairing my main PC, bringing up a new one and learning Vista. I'd much rather be working on green issues.
While I have been on hold for a support person, (a week at least) I have been hatching a new idea. This idea stems from my belief that a portion of going green is easy. I also know that a portion of going green is very, very hard.
The reason we care is that none of us are really capable of a zero footprint. We humans will have an impact, the only question is how much and what is proper?
So I like to think of the things that count, as GEWS. Gas, Electric Water and Sewer. We also have garbage and gasoline. If you take all these, they encompass much of our footprint. We could add jet fuel and batteries and stuff we buy but that's all a bit too complex.
So taking these six simple things and reducing them 30% is a big step. In fact, I believe it's a big enough step! If we could all do 30% it would make a huge difference to our planet!
My experience tells me that 30% is a good goal and requires some effort and ongoing vigilance, but not big life changes. We can live our lives at 30% less just by being smart, eliminating waste and sticking to that goal.
Let's look at each part of our footprint individually:
Gas (Natural Gas) - Depending on what your appliances are running on, this one may be one of the tougher ones to reduce 30%. It means lowering the thermostat on the water heater. Getting a programmable thermostat for the furnace. Insulate the water heater and the hot water pipes and seal up the house. I am at 28% for the last six months mainly because I had a recirculating hot water pump that's now on a timer.
Electricity - This is easier because we have so many things that run on electricity. Limiting the time things are on, using a small oven, and again using a programmable thermostat are the basics. I am at 26.5% and going up.
Water - I made some big changes in my sprinkler system, added a low flow washer to our shower and let the yellow mellow. I am at 32% for this item.
Sewer - This item is a reflection of your water use in Dallas. In theory, a water reduction should always reduce sewer use. I don't track it because mine was artificially low last year as I found out right before I picked up the phone to call the city and complain. So mine is higher this year, but through no fault of my own.
Garbage - Recycling/composting - I think 30% is too easy if you aren't really paying attention to what you throw in the bin. If you recycle to the letter of the law, 30%s a good number and the composting is just gravy. Mulching in all my fall leaves gets me way ahead.
Gasoline - Here I still have a problem. My car eats a lot of gas (22 MPG). But to get 30% saving means I only have to get to 29 MPG. That's reasonable for a large four door sedan.
So we can all do 30%. It's really not hard and the money saved might surprise you. My average savings per month this year is $150.58 over the same period last year.
Bottom Line - The first 30% is the right thing to do, pretty easy and has a great return on investment.
Now I am beginning to look at the second 30%. This is much harder and requires much more money with longer paybacks. It includes new sprinkler equipment, some new super windows, possibly a whole house fan, a duct blaster test, new recessed light fixtures, possibly a radiant barrier for the attic, and maybe buying less stuff, or stuff with a lot less packaging.
The last 30% is photovoltaics, geothermal heat pumps, solar hot water, hybrid small car, new windows throughout, large water cisterns and pumps, grey water recycling. landscape change to xeriscape and a winning lottery ticket.
While I have been on hold for a support person, (a week at least) I have been hatching a new idea. This idea stems from my belief that a portion of going green is easy. I also know that a portion of going green is very, very hard.
The reason we care is that none of us are really capable of a zero footprint. We humans will have an impact, the only question is how much and what is proper?
So I like to think of the things that count, as GEWS. Gas, Electric Water and Sewer. We also have garbage and gasoline. If you take all these, they encompass much of our footprint. We could add jet fuel and batteries and stuff we buy but that's all a bit too complex.
So taking these six simple things and reducing them 30% is a big step. In fact, I believe it's a big enough step! If we could all do 30% it would make a huge difference to our planet!
My experience tells me that 30% is a good goal and requires some effort and ongoing vigilance, but not big life changes. We can live our lives at 30% less just by being smart, eliminating waste and sticking to that goal.
Let's look at each part of our footprint individually:
Gas (Natural Gas) - Depending on what your appliances are running on, this one may be one of the tougher ones to reduce 30%. It means lowering the thermostat on the water heater. Getting a programmable thermostat for the furnace. Insulate the water heater and the hot water pipes and seal up the house. I am at 28% for the last six months mainly because I had a recirculating hot water pump that's now on a timer.
Electricity - This is easier because we have so many things that run on electricity. Limiting the time things are on, using a small oven, and again using a programmable thermostat are the basics. I am at 26.5% and going up.
Water - I made some big changes in my sprinkler system, added a low flow washer to our shower and let the yellow mellow. I am at 32% for this item.
Sewer - This item is a reflection of your water use in Dallas. In theory, a water reduction should always reduce sewer use. I don't track it because mine was artificially low last year as I found out right before I picked up the phone to call the city and complain. So mine is higher this year, but through no fault of my own.
Garbage - Recycling/composting - I think 30% is too easy if you aren't really paying attention to what you throw in the bin. If you recycle to the letter of the law, 30%s a good number and the composting is just gravy. Mulching in all my fall leaves gets me way ahead.
Gasoline - Here I still have a problem. My car eats a lot of gas (22 MPG). But to get 30% saving means I only have to get to 29 MPG. That's reasonable for a large four door sedan.
So we can all do 30%. It's really not hard and the money saved might surprise you. My average savings per month this year is $150.58 over the same period last year.
Bottom Line - The first 30% is the right thing to do, pretty easy and has a great return on investment.
Now I am beginning to look at the second 30%. This is much harder and requires much more money with longer paybacks. It includes new sprinkler equipment, some new super windows, possibly a whole house fan, a duct blaster test, new recessed light fixtures, possibly a radiant barrier for the attic, and maybe buying less stuff, or stuff with a lot less packaging.
The last 30% is photovoltaics, geothermal heat pumps, solar hot water, hybrid small car, new windows throughout, large water cisterns and pumps, grey water recycling. landscape change to xeriscape and a winning lottery ticket.
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