Battery back ups for houses

In 2021, I ordered 3 different home batteries (from Generac, Sonnen and EnPhase at about 15kWh each) to go with existing and new solar-panel arrays (this is how you get the SMART MA subsidy for batteries) for our house and two rental properties we own. THIS IS VERY COMPLEX!

•I was faced with replacing propane powered back-up generators at all 3 houses

•Would have cost $5k per house plus $500 a year for maintenance/service

•The batteries were about $20k each after installation, none was a Tesla Powerwall

•Powerwall cannot both run the house and charge from solar panels together making it useless during lengthy power outages in winter. It is designed for power arbitrage (CA), not back-up generation (MA)! This can be alleviated if you buy the Tesla inverter. A friend just installed two Powerwalls plus this inverter and it cost $23,500 in MA. 

•The batteries+arrays were profitable (5-10% IRR) vs. arrays alone (10-15% IRR)

•A 15kWh battery will run my house (but not the heat pumps) for a day

•Not enough! We have had 3-day power outages at our house

•In late 2021 I ordered the Lightening (with a 100kWh battery = 7 PWs)

•In 2023 I cancelled all 3 battery orders. With V2H on most vehicles by 2025, don’t get a back-up generator or house battery – get V2H!

The V2H and V2G capabilities of EVs are one of the main reasons we need a time of day tariff for electricity in MA. CA has it and it is essential to reducing peaker plant usage on hot summer afternoons as well as saving money by charging your battery at night and using it during the day.

The introduction of this tariff would have a huge impact on greenhouse gas emissions. It would also allow low-income households to reduce their electric bills substantially by, for instance running the dishwasher and clothes dryer (and charging their EVs) at night.

David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

David Green – the “Green Guru”

David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

The highly-acclaimed book “Zero Carbon Home”

How David Green, the "Green Guru" cut his home's carbon emissions and utility bills to zero by adding heat pumps, insulation, triple-pane windows and solar panels to make a 15% return on investment. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

How we cut our home’s carbon emissions to zero

How David Green, the "Green Guru" cut his home's utility bills to zero by adding heat pumps, insulation, triple-pane windows and solar panels to make a 15% return on investment. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

How we cut our home’s utility bills to zero

Our solar panels on the roof of our house. Solar panels are one of the Fab Four of heat pumps, insulation, triple-pane windows and solar panels that got our house to net zero. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

Solar panels on the roof of our house

Our heat pumps at our house. Heat pumps are one of the Fab Four of heat pumps, insulation, triple-pane windows and solar panels that got our house to net zero. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living. Our Bosch heat pumps replaced our ancient AC units. They fit into the same space and electrical breakers as the old AC units. They are saving us about $3,000 a year in heating oil, even after the extra electricity they take.

Our heat pumps

This is the insulation on the roof of our house. The pink fiberglass is 10" thick and has an R-value of about R30. The grey boards are rigid foam ISO boards at about R10 each. Insulation is one of the Fab Four of heat pumps, insulation, triple-pane windows and solar panels that got our house to net zero. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

Fiberglass and ISO board insulation on the roof of our house

These are the triple-pane windows we installed in our living room. Triple-pane windows are one of the Fab Four of heat pumps, insulation, triple-pane windows and solar panels that got our house to net zero. Our new triple glazed windows replaced a mix of 1970's vintage single and double-pane units. The insulating value of the new windows is about 3x that of the old ones. Although it is hard to quantify, our new triple-glazed windows have transformed the look and feel of the house, plus we no longer have to sit under blankets to avoid the cold drafts off the old windows in winter. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

Triple-pane windows in our living room

Useful links:

The Easiest Way to Calculate Your Home’s Carbon Footprint:https://greenzerocarbonhome.com/2018/07/what-is-the-carbon-footprint-of-natural-gas-heating-oil-propane-and-coal/

Written Answers to over 300 Questions about Zero Carbon Homes:https://greenzerocarbonhome.com/webinar-questions-and-answers/

Finance and Net Zero Energy Terms explained: https://greenzerocarbonhome.com/energy-and-finance-terms-explained/

Zero Carbon Home Website Home Page:                https://greenzerocarbonhome.com

Database of State Incentive for Renewable Energy (DSIRE) https://www.dsireusa.org

Published articles on Zero Carbon and Net Zero Energy:

Department of Energy, EnergySage, “Zero Carbon Home”https://www.energysage.com/project/7230/zero-carbon-home/

Zero Energy Project, “My Zero Energy Retrofit beats my 401k”https://zeroenergyproject.org/2018/09/23/my-zero-energy-retrofit-beats-my-401k/

Cool Effect, “Mr. Green’s Zero Carbon Home”         https://www.cooleffect.org/content/news/green-testimonial?utm_source=Cool_Effect_CRM&utm_medium=EMAIL&utm_campaign=20180814Engage_Testimonial&utm_content=green_CTA

Green Energy Times, “My Zero Energy Pool is a Great Investment!” http://www.greenenergytimes.org/wp-content/uploads/2019/05/GET_May-2019.pdf

Published Presentations on Zero Carbon Zero Bills:

To see a 3-minute interview of David Green by NBC Boston anchor Joy Lim Nakrin, please click here:TV interview

To see a 20-minute TED talk at Harvard Business School, please click here: TED Talk

You can watch a recorded version of my Zero Carbon, Zero Bills webinar here: Zero Carbon, Zero Bills Webinar

Reviews of my “Zero Carbon, Zero Bills” webinar included, “Minute-for-minute, point-for-point, one of the best webinars I have ever attended. Thank you!”, “David is a true inspiration and asset to our community. He inspired us to get solar panels and a new front door”, “This is like a masterclass in ZeroCarbon”, “Thank you soooo much for the sensible advice and your fabulous resources!!” and, although this next comment is a little flowery, it does express the sentiment of many other comments, “Your contribution to Greening America is great and will probably help our survival as a species a bit longer than expected”.

Vehicle to Home and Vehicle to Grid.

Vehicle to Home and Vehicle to Grid.

V2H (vehicle-to-home) uses your EV to replace your back-up generator

V2G (vehicle-to-grid) uses your EV to reduce peaker-plant usage on the grid

•not useful in MA, because we have no (time of day) TOD electrical tariff (there should be!!). A TOD tariff is where the price of electricity is higher during periods of high demand (usually mid afternoons in summer when people use AC) and lower at night. CA has this type of tariff but MA does not. 

V2H is already on Nissan Leaf (with charge station) and Ford F150 Lightening. 

•It will be standard on Teslas in 2025, all GM EVs in 2026, Kia EV9 in 2024

•This could be accelerated by legislation requiring it, but a bill in CA recently failed

My Ford F-150 Lightening has 100kWh of storage (7x a Tesla Powerwall!), it has 4 x 110V outlets in the truck bed. These can run things like: circular saws, lights, refrigerator, microwave, espresso – awesome tailgating/movies! Plus 220V for V2H. 

•It will run my house for 5 days (without the heat pumps), a Powerwall would run it for a day. The F150 Lightening could also charge my Tesla.

•The Ford F150 Lightening costs $75k less $7.5k FTC and $7.5k MA rebate = $60k. Regular Ford F150 is about $45k plus $62k for 7 Powerwalls(=100kWh) = $107k

•The Ford F150 Lightening is a huge battery on 4 wheels.  It is also a very nice truck! It has been on order for 2 years. Don’t get a house battery or new generator – get V2H!

David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

David Green – the “Green Guru”

David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

The highly-acclaimed book “Zero Carbon Home”

How David Green, the "Green Guru" cut his home's carbon emissions and utility bills to zero by adding heat pumps, insulation, triple-pane windows and solar panels to make a 15% return on investment. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

How we cut our home’s carbon emissions to zero

How David Green, the "Green Guru" cut his home's utility bills to zero by adding heat pumps, insulation, triple-pane windows and solar panels to make a 15% return on investment. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

How we cut our home’s utility bills to zero

Our solar panels on the roof of our house. Solar panels are one of the Fab Four of heat pumps, insulation, triple-pane windows and solar panels that got our house to net zero. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

Solar panels on the roof of our house

Our heat pumps at our house. Heat pumps are one of the Fab Four of heat pumps, insulation, triple-pane windows and solar panels that got our house to net zero. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living. Our Bosch heat pumps replaced our ancient AC units. They fit into the same space and electrical breakers as the old AC units. They are saving us about $3,000 a year in heating oil, even after the extra electricity they take.

Our heat pumps

This is the insulation on the roof of our house. The pink fiberglass is 10" thick and has an R-value of about R30. The grey boards are rigid foam ISO boards at about R10 each. Insulation is one of the Fab Four of heat pumps, insulation, triple-pane windows and solar panels that got our house to net zero. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

Fiberglass and ISO board insulation on the roof of our house

These are the triple-pane windows we installed in our living room. Triple-pane windows are one of the Fab Four of heat pumps, insulation, triple-pane windows and solar panels that got our house to net zero. Our new triple glazed windows replaced a mix of 1970's vintage single and double-pane units. The insulating value of the new windows is about 3x that of the old ones. Although it is hard to quantify, our new triple-glazed windows have transformed the look and feel of the house, plus we no longer have to sit under blankets to avoid the cold drafts off the old windows in winter. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

Triple-pane windows in our living room

Useful links:

The Easiest Way to Calculate Your Home’s Carbon Footprint:https://greenzerocarbonhome.com/2018/07/what-is-the-carbon-footprint-of-natural-gas-heating-oil-propane-and-coal/

Written Answers to over 300 Questions about Zero Carbon Homes:https://greenzerocarbonhome.com/webinar-questions-and-answers/

Finance and Net Zero Energy Terms explained: https://greenzerocarbonhome.com/energy-and-finance-terms-explained/

Zero Carbon Home Website Home Page:                https://greenzerocarbonhome.com

Database of State Incentive for Renewable Energy (DSIRE) https://www.dsireusa.org

Published articles on Zero Carbon and Net Zero Energy:

Department of Energy, EnergySage, “Zero Carbon Home”https://www.energysage.com/project/7230/zero-carbon-home/

Zero Energy Project, “My Zero Energy Retrofit beats my 401k”https://zeroenergyproject.org/2018/09/23/my-zero-energy-retrofit-beats-my-401k/

Cool Effect, “Mr. Green’s Zero Carbon Home”         https://www.cooleffect.org/content/news/green-testimonial?utm_source=Cool_Effect_CRM&utm_medium=EMAIL&utm_campaign=20180814Engage_Testimonial&utm_content=green_CTA

Green Energy Times, “My Zero Energy Pool is a Great Investment!” http://www.greenenergytimes.org/wp-content/uploads/2019/05/GET_May-2019.pdf

Published Presentations on Zero Carbon Zero Bills:

To see a 3-minute interview of David Green by NBC Boston anchor Joy Lim Nakrin, please click here:TV interview

To see a 20-minute TED talk at Harvard Business School, please click here: TED Talk

You can watch a recorded version of my Zero Carbon, Zero Bills webinar here: Zero Carbon, Zero Bills Webinar

Reviews of my “Zero Carbon, Zero Bills” webinar included, “Minute-for-minute, point-for-point, one of the best webinars I have ever attended. Thank you!”, “David is a true inspiration and asset to our community. He inspired us to get solar panels and a new front door”, “This is like a masterclass in ZeroCarbon”, “Thank you soooo much for the sensible advice and your fabulous resources!!” and, although this next comment is a little flowery, it does express the sentiment of many other comments, “Your contribution to Greening America is great and will probably help our survival as a species a bit longer than expected”.

Low E coatings on a door

Question:

We are installing a new wood and glass door — with the style of 15 panes of double glaze glass (sort of a traditional style door) — and, on top of that a new single-glaze storm door.  The question is, which door is best to put Low E glass in? The outermost storm door, or the inner double-glaze wood door? This will be on the south side of the house.  (and would it make any difference if the inner wood-glass door is 15 actual panes or simulated divided lites?)

The architect suggested we use Low E glass, as that side of the house is sunny, but he doesn’t know which door is best to put the Low E into.  He thought the inner wood door might be the best place, as it has a tighter seal and is two layers of glass, but he doesn’t know for sure.  I thought maybe the outermost door (the storm door) is the best place for Low E, so it deflects heat before it enters the few inches inward into the building envelope and heats up the space between the storm door and the multi-pane glass/wood door.  But, I’m just guessing.  Also, in summer, the top 1/2 of the storm door won’t have glass, but will have a screen, so Low E on the storm door would be only on the lower half of the door for about 1/2 of the year. (there will be a small overhanging roof, but only about 3 ft of overhang)

So, with that info, what might the science really suggest is the right place to put the Low E glass?

Answer: With a south facing door with a 3’ overhang you have about the optimal set up for gaining the maximum heat from the sun in winter (when the sun is low in the sky) and still preventing overheating in summer because the sun is high the the sky and the overhang shades the glass. In our house in these circumstances we used no lowE coating on the windows and patio doors. This allows a lot of sun into the house on sunny winter days which makes lovely places to warm up in the sun. We don’t have pets, but I have heard that pets love spaces like this to curl up in the warmth! So I suggest just clear glass, no lowE coating. This is for the outside. You still want the lowE i89 coating on the inside because this reflects heat (infra red light) back into the house keeping it much warmer in winter. The storm door will not add much insulation because air moves behind it. Storm doors protect the real door from wind and rain, they do not add much insulation. If it is possible to get the door with triple-pane panels that would be better. The insulation value of a glass door with simulated divided lites will be higher than that of door with real wood strips dividing 15 smaller panes of glass because even a plain double glazed window is about R2 whereas wood is about R1 per inch and the depth of the wood is about an inch, hence the wood is the most thermally leaky part of the door. 

I hope this helps!

David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

David Green – the “Green Guru”

David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

The highly-acclaimed book “Zero Carbon Home”

How David Green, the "Green Guru" cut his home's carbon emissions and utility bills to zero by adding heat pumps, insulation, triple-pane windows and solar panels to make a 15% return on investment. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

How we cut our home’s carbon emissions to zero

How David Green, the "Green Guru" cut his home's utility bills to zero by adding heat pumps, insulation, triple-pane windows and solar panels to make a 15% return on investment. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

How we cut our home’s utility bills to zero

Our solar panels on the roof of our house. Solar panels are one of the Fab Four of heat pumps, insulation, triple-pane windows and solar panels that got our house to net zero. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

Solar panels on the roof of our house

Our heat pumps at our house. Heat pumps are one of the Fab Four of heat pumps, insulation, triple-pane windows and solar panels that got our house to net zero. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living. Our Bosch heat pumps replaced our ancient AC units. They fit into the same space and electrical breakers as the old AC units. They are saving us about $3,000 a year in heating oil, even after the extra electricity they take.

Our heat pumps

This is the insulation on the roof of our house. The pink fiberglass is 10" thick and has an R-value of about R30. The grey boards are rigid foam ISO boards at about R10 each. Insulation is one of the Fab Four of heat pumps, insulation, triple-pane windows and solar panels that got our house to net zero. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

Fiberglass and ISO board insulation on the roof of our house

These are the triple-pane windows we installed in our living room. Triple-pane windows are one of the Fab Four of heat pumps, insulation, triple-pane windows and solar panels that got our house to net zero. Our new triple glazed windows replaced a mix of 1970's vintage single and double-pane units. The insulating value of the new windows is about 3x that of the old ones. Although it is hard to quantify, our new triple-glazed windows have transformed the look and feel of the house, plus we no longer have to sit under blankets to avoid the cold drafts off the old windows in winter. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.

Triple-pane windows in our living room

Useful links:

The Easiest Way to Calculate Your Home’s Carbon Footprint:https://greenzerocarbonhome.com/2018/07/what-is-the-carbon-footprint-of-natural-gas-heating-oil-propane-and-coal/

Written Answers to over 300 Questions about Zero Carbon Homes:https://greenzerocarbonhome.com/webinar-questions-and-answers/

Finance and Net Zero Energy Terms explained: https://greenzerocarbonhome.com/energy-and-finance-terms-explained/

Zero Carbon Home Website Home Page:                https://greenzerocarbonhome.com

Database of State Incentive for Renewable Energy (DSIRE) https://www.dsireusa.org

Published articles on Zero Carbon and Net Zero Energy:

Department of Energy, EnergySage, “Zero Carbon Home”https://www.energysage.com/project/7230/zero-carbon-home/

Zero Energy Project, “My Zero Energy Retrofit beats my 401k”https://zeroenergyproject.org/2018/09/23/my-zero-energy-retrofit-beats-my-401k/

Cool Effect, “Mr. Green’s Zero Carbon Home”         https://www.cooleffect.org/content/news/green-testimonial?utm_source=Cool_Effect_CRM&utm_medium=EMAIL&utm_campaign=20180814Engage_Testimonial&utm_content=green_CTA

Green Energy Times, “My Zero Energy Pool is a Great Investment!” http://www.greenenergytimes.org/wp-content/uploads/2019/05/GET_May-2019.pdf

Published Presentations on Zero Carbon Zero Bills:

To see a 3-minute interview of David Green by NBC Boston anchor Joy Lim Nakrin, please click here:TV interview

To see a 20-minute TED talk at Harvard Business School, please click here: TED Talk

You can watch a recorded version of my Zero Carbon, Zero Bills webinar here: Zero Carbon, Zero Bills Webinar

Reviews of my “Zero Carbon, Zero Bills” webinar included, “Minute-for-minute, point-for-point, one of the best webinars I have ever attended. Thank you!”, “David is a true inspiration and asset to our community. He inspired us to get solar panels and a new front door”, “This is like a masterclass in ZeroCarbon”, “Thank you soooo much for the sensible advice and your fabulous resources!!” and, although this next comment is a little flowery, it does express the sentiment of many other comments, “Your contribution to Greening America is great and will probably help our survival as a species a bit longer than expected”.

 

Electric Vehicles, EVs, Vehicle to House (V2H) and Vehicle to Grid (V2G)

• In 2020 I bought a Tesla model S Long Range

•50,000 miles in 3.5 years. It is our preferred car for long-distance travel

•The Tesla Supercharging network is convenient and reliable. GM & Ford will have access to it in ‘24

•We stop every 150 miles or so (every 2-3 hours) for coffee/stretch & add 100 miles of range in 15 mins. There is NO range anxiety. 360-mile range on full charge.

•It is more comfortable than a BMW 3 series or BMW X5 and has more storage space

•Our son went to university in one trip with his bike on the roof and a passenger

•A Tesla Model S costs about $85k. which is still very expensive. However a Model 3 now costs about $26k after the federal tax credit and new MOR-EV MA rebates. For example: The list price of a new Tesla Model 3 is $37k – $7.5k FTC., – $3.5k MA = $26k which means a lease rate of around $375 a month. A new BMW 3 Series has a list price of $42k. So a new Tesla Model 3 is far cheaper to buy than a BMW 3 series. Also, a new Ford F150 Lightening costs $75k – $7.5k federal tax credit – $7.5k MA = $60k. A new gas-powered F150 is $45k.

•The new BYD Atto3 has a 270m range and is priced at under $20k (not available in US yet, already top selling EV in Sweden). A new Toyota Corolla costs over $20k. 

EVs are now cheaper to buy than gas cars!

•On utility electricity (35c/kWh) I can go to NYC (200 miles) for $18 or $4 at solar-panel rates (8c/kWh). BMW 3 Series at 20 mpg & $4/gallon costs $40. Using electricity from my solar panels, I save $2,700/yr. or about $225/mo. a year on gas. The net present value of this (NPV) @3%=$90k. So the savings on gas are worth more over the lifetime of ownership that what I paid upfront for the Model S which was $85k. You can lease a new Model 3 for a net cost of $150/mo. 

If you subtract the monthly savings on gas (about $225) from the lease rate for Model 3 of about $375 a month you have a net cost to drive of about $150 per month. The cheapest lease I can find for a gas-powered vehicle is $269/month for a Chevrolet Equinox.

EVs are now cheaper to drive than gas cars.!

•I have spent zero on maintenance / servicing of my Tesla Model S in 3.5 years. Except: tires last 20k miles not 40k. 

EVs are now cheaper to buy,  run,  & maintain than gas cars. 

Vehicle to Home and Vehicle to Grid.

V2H (vehicle-to-home) uses your EV to replace your back-up generator

V2G (vehicle-to-grid) uses your EV to reduce peaker-plant usage on the grid

•not useful in MA, because we have no (time of day) TOD electrical tariff (there should be!!). A TOD tariff is where the price of electricity is higher during periods of high demand (usually mid afternoons in summer when people use AC) and lower at night. CA has this type of tariff but MA does not.

V2H is already on Nissan Leaf (with charge station) and Ford F150 Lightening. 

•It will be standard on Teslas in 2025, all GM EVs in 2026, Kia EV9 in 2024

•This could be accelerated by legislation requiring it, but a bill in CA recently failed

My Ford F-150 Lightening has 100kWh of storage (7x a Tesla Powerwall!), it has 4 x 110V outlets in the truck bed. These can run things like: circular saws, lights, refrigerator, microwave, espresso – awesome tailgating/movies! Plus 220V for V2H. 

•It will run my house for 5 days (without the heat pumps), a Powerwall would run it for a day. The F150 Lightening could also charge my Tesla.

•The Ford F150 Lightening costs $75k less $7.5k FTC and $7.5k MA rebate = $60k. Regular Ford F150 is about $45k plus $62k for 7 Powerwalls(=100kWh) = $107k

•The Ford F150 Lightening is a huge battery on 4 wheels.  It is also a very nice truck! It has been on order for 2 years. Don’t get a house battery or new generator – get V2H!

In 2021, I ordered 3 different home batteries (from Generac, Sonnen and EnPhase at about 15kWh each) to go with existing and new solar-panel arrays (this is how you get the SMART MA subsidy for batteries) for our house and two rental properties we own. THIS IS VERY COMPLEX!

•I was faced with replacing propane powered back-up generators at all 3 houses

•Would have cost $5k per house plus $500 a year for maintenance/service

•The batteries were about $20k each after installation, none was a Tesla Powerwall

•Powerwall cannot both run the house and charge from solar panels together making it useless during lengthy power outages in winter. It is designed for power arbitrage (CA), not back-up generation (MA)! This can be alleviated if you buy the Tesla inverter. A friend just installed two Powerwalls plus this inverter and it cost $23,500 in MA.

•The batteries+arrays were profitable (5-10% IRR) vs. arrays alone (10-15% IRR)

•A 15kWh battery will run my house (but not the heat pumps) for a day

•Not enough! We have had 3-day power outages at our house

•In late 2021 I ordered the Lightening (with a 100kWh battery = 7 PWs)

•In 2023 I cancelled all 3 battery orders. With V2H on most vehicles by 2025, don’t get a back-up generator or house battery – get V2H!

The V2H and V2G capabilities of EVs are one of the main reasons we need a time of day tariff for electricity in MA. CA has it and it is essential to reducing peaker plant usage on hot summer afternoons as well as saving money by charging your battery at night and using it during the day.

The introduction of this tariff would have a huge impact on greenhouse gas emissions. It would also allow low-income households to reduce their electric bills substantially by, for instance running the dishwasher and clothes dryer (and charging their EVs) at night.

Tesla Model S is our preferred car for long distance travel – there is no range anxiety with the Supercharging network

Our Tesla Model S is our preferred vehicle for driving long distances (like down to NY and NJ) from Dover, MA which is about 200 miles. The Tesla Supercharging network is easy to use, fast, and reliable. We stop about every 150 mile or so for a stretch and cup of coffee and in 15 mins we have added 100 miles of range. There are at least 6 supercharging stations (each with about 8-12 individual chargers) between here and NY/NJ. Only once in 3 years have I found all of the chargers in use when we arrived. A space opened up in 5 mins. I do not have range anxiety in my Tesla and it is cheaper to drive than any gas car. Because I charge it from my solar panels it also has a zero carbon footprint. It is also very comfortable for 5 adults whereas the BMW3 series and X5 (SUV) have back seats that are definitely uncomfortable for 5 adults. Everyone detests being the one who needs to sit in the center seat on the ridge above the transmission. Both Ford and GM have announced that their EVs will be able to use the Tesla Supercharging network “next year” and somehow I doubt it will go smoothly, so yes there may still be some justification for range anxiety in a Ford or GM vehicle, but remember those vehicles can also access all Chargepoint, EVGo and other non-Tesla networks so in practice they will have access to every charging station in the USA.

Scope 1 Scope 2 and scope 3 emissions for houses

Net zero for houses does not include scope 3, just scope 1 (emissions from what you burn on site) and scope 2 (emissions from electricity used on site but generated offsite) less any excess power (measured over the whole year) that you contribute to the grid.

In my opinion scope 3 is a huge and meaningless distraction. If everyone (businesses as well as houses) took care of their scope 1 and scope 2 emissions there would not be any scope 3 emissions.

When you burn the coal for heat you cause scope 1 emissions. When a power station burns it to make electricity that you then use you are generating scope 2 emissions. The only scope 3 emissions you generate by burning coal are emissions generated by mining and transporting it. These are not trivial, but not huge either. If coal mining companies used electric-powered miners and electric powered trains (and both were powered by renewable electricity) their scope 3 emissions would be zero. See what I mean?

Coal will go out of use for one reason and one reason only: cost. It now costs more to generate electricity from coal than to generate it from solar or wind. Energy is the ultimate commodity market. The lowest-cost player wins and winner takes all. It is game over for coal. Oil will follow as EV penetration becomes significant, likely, within the next few years. Natural gas will follow that. Zero carbon is now inevitable. The pace is to be determined, but I believe EVs have now hit the inflection point. Housing is still lagging. 

Massachusetts Electric Vehicle (EV) Subsidies MOR-EV program

Massachusetts just (9/27/23) announced its HUGE new rebates for buying or leasing electric vehicles (EVs).

These new MA EV incentives are huge and are in addition to the Federal tax credits. On cars, the new MA incentive is $3,500 and on trucks (like the F150 Lightening I have on order) it is $7,500. 

On a new Tesla Model 3, which lists for $37,000, the net price is now $26,000. A new Toyota Corolla is $22,000. Corolla’s cost about $4,000 in maintenance in the first 10 years. The Model 3 will cost nothing.  So, including maintenance the Tesla Model 3 and the Toyota Corolla cost the same. The Tesla Model 3 will save about $800 a year on gas (even when charged at todays very high electricity prices) compared to the Corolla. So, over its first 10 years, the Tesla Model 3 is now about $8,000 cheaper than a Toyota Corolla. The Tesla Model 3 will save far more money if it is charged from rooftop solar panels on your house which can generate electricity for about 5-8c/kWh compared to our local utilities which charge about 40c/kWh. On our solar electricity, I can travel the 200 miles from Dover, MA to New York City for about $4. They Greyhound costs $26, is uncomfortable and spews CO2 and pollution every mile of the way.

The internal combustion powered the advances in the last century. Thank you for all you have done for civilization internal combustion engines, but it now game over and time to move on. Solar, heat pumps and EVs. Plus insulation and triple-pane windows on your house. That is the recipe for getting to net zero.

This is the inflection point we have been working so hard to reach! Congrats to all who have been involved in creating both the federal (IRA) act and the MA one. This is a huge victory for us and the planet!

What incentives are available through MOR-EV?
As of August 8, 2023, MOR-EV has added new incentives for EVs:

  • A $3,500 rebate for the purchase or lease of a new electric car with a total MSRP of up to $55,000 or a used electric car with final sales price up to $40,000.
  • A $7,500 rebate for the purchase or lease of a new electric truck with a total MSRP of up to $80,000.
  • An additional rebate of $1,500 for people who participate in certain income-qualified programs.

Biotechnology – The Technology of Increased Human Lifespan

Longevity. Increasing lifespan. Biotechnology. Stem Cells. Revolutions in medicine, agriculture and sanitation increased the human population to 8 billion and increased human lifespan from 30 years to 80 years in only the last 150 years.
Biotechnology the technology of life.

Webinar by David Green (who founded two biotech companies, was CEO of both and took both public on NASDAQ) on how medical, sanitary and agricultural revolutions led to 8 billion humans on Earth and a fifty-year increase in human lifespan in just the last 150 years. Will the trend continue and will your grandchildren live to 150?

This webinar was created for students at Dover-Sherborn High School in March 2023. It is available on YouTube by clicking here: https://youtu.be/jsQ7KueGicg

In addition to founding and being CEO of two biotech companies, both of which he took public on NASDAQ, David Green cut his home’s carbon emissions to zero and is making a 15% return on his investments in heat pumps, insulation, triple-pane windows and solar panels. You can read about his experience on this website.

You can download the slides for my presentation here:

Zero Carbon for a house for rent

Q: This question is about renting out a property that is zero carbon.

I saw that you have rental properties that are zero carbon. How did you get those to work financially? I’d like to create a zero carbon rentals, and the ways I can imagine getting it to work financially:

1. Include electricity in the rent (charging enough to pay off the solar panels, heat pumps in a reasonable period). The drawback there is it doesn’t incentivize energy conservation, unless there was a cap at e.g., #### kwHr/month on average (the first one I’d convert to such a rental is the home I’m living in, so I’ll have a pretty good understanding of energy usage).

2. Charge a premium because it’s a net zero house, but they still pay the electric bills.

3. Charge a monthly fee (e.g., “a climate-friendly house” fee, and educate them about how they recover some of those costs with reduced electric bills) such that the heat pump and solar electric system pay for themselves in e.g., 10 years.

I live in a state that doesn’t do much to incentivize zero carbon, but fortunately my city (Columbia, Missouri) has both net metering, and rebates and low-interest loans (3-5% for 5-10 years) for heat pumps, energy efficiency measures, and solar electric.

I would appreciate any perspective you can share.

A:

Hi Terry, neither of my rental properties is zero carbon, at least not yet. 

The first one is almost impossible to insulate due to having brick walls with no cavity and very nice old oak paneling on the inside. We have added triple-pane windows, some insulation in the basement, heat pumps and a 25kW array. It is still not at net zero. I am waiting for a wall injection system that drills through the mortar rather than the bricks before I can insulate it without having to either drill the bricks (which is prohibitively expensive) or take off the oak panels. It is probably about 70% of the way there. We charge market-rate rent for the place (I found I could not charge any premium for bring “green” though I do think it creates a preference at the market price) but I add the solar production to the electricity consumption from the grid and charge the tenant for this. I am making solar electricity at around 10c/kWh and I am selling it to the tenant at utility rates currently around 40c/kWh and long term perhaps 25c/kWh. I sell the tenant about 20k kWh a year which at 15c/kWh is $3,000 a year which is about a 5% increase in the rent. So I do get paid something, but probably not enough to justify all the investment. However the value of the house has gone up considerably and I think I would get my investment back if we sold it. Academic research strongly supports this conclusion. 

On our other rental property we are making progress but it is still a long way off. We are just about to replace the HVAC system ( the furnace broke and the AC units are 25-years old) and are considering geothermal. At a minimum we will do ASHP. The attic needs insulating and draft sealing but I have not done it yet due to dampness in the basement. If I draft seal it now I will just get mold in the attic. Hence I need to put a sump pump in the basement first. This is coming this month.  I already have installed a heat-pump hot water tank which is doing a nice job of dehumidifying the basement. This house is too shaded, and the roof lines too chopped up, for solar. Hence I have bought 12,000 kWh a year from an installer of big solar arrays in MA. In MA, the net-metering law allows you to transfer excess credits to other meters. There is now a whole industry doing this because it is highly profitable. You generate zero-carbon electricity from utility-scale solar arrays at about 5c/kWh and sell it at a 12% discount to utility rates or about 35c/kWh. That’s a fat profit!

This second house is not currently rented. I doubt I can get a premium for the “low carbon” status. I might be able to once it is finished and has zero-carbon status. I have no doubt I would get my money back if I sold it with zero carbon emissions and zero utility bills. I think I could get a rent premium once it is there because of the zero utility bills. The utility bills are about $12k a year and that would represent a 12% premium to market rent. 

I hope this helps. Please let me know how you get on with zero carbon rentals!

Heat pumps insulation triple glazed windows and solar panels Zero Carbon Home author David Green
Cut your carbon emissions and utility bills to zero, I have done it
How David Green, the "Green Guru" cut his home's carbon emissions and utility bills to zero by adding heat pumps, insulation, triple-pane windows and solar panels to make a 15% return on investment.
How David Green, the “Green Guru” cut his home’s carbon emissions and utility bills to zero by adding heat pumps, insulation, triple-pane windows and solar panels to make a 15% return on investment.
How David Green, the "Green Guru" cut his home's carbon emissions and utility bills to zero by adding heat pumps, insulation, triple-pane windows and solar panels to make a 15% return on investment. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the "Green Guru" for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.
How David Green, the “Green Guru” cut his home’s carbon emissions and utility bills to zero by adding heat pumps, insulation, triple-pane windows and solar panels to make a 15% return on investment. David Green is the author of the books Zero Carbon Home and Zero Carbon Pool. He is also the author and presenter of the webinar Zero Carbon, Zero Bills. He is recognized as the “Green Guru” for his expertise in energy efficiency, profitable ways to cut carbon emissions and save money, and the design of houses for net-zero living.
Book energy efficiency Zero Carbon Home 2020 edition front cove. Profitable ways to cut your home's carbon emissions and bills. How to get a net-zero-carbon house. By Green Guru David Green.
Zero Carbon Home paperback book front cover

Useful links:

The Easiest Way to Calculate Your Home’s Carbon Footprint:https://greenzerocarbonhome.com/2018/07/what-is-the-carbon-footprint-of-natural-gas-heating-oil-propane-and-coal/

Written Answers to over 300 Questions about Zero Carbon Homes:https://greenzerocarbonhome.com/webinar-questions-and-answers/

Finance and Net Zero Energy Terms explained: https://greenzerocarbonhome.com/energy-and-finance-terms-explained/

Zero Carbon Home Website Home Page:                https://greenzerocarbonhome.com

Database of State Incentive for Renewable Energy (DSIRE) https://www.dsireusa.org

Published articles on Zero Carbon and Net Zero Energy:

Department of Energy, EnergySage, “Zero Carbon Home”https://www.energysage.com/project/7230/zero-carbon-home/

Zero Energy Project, “My Zero Energy Retrofit beats my 401k”https://zeroenergyproject.org/2018/09/23/my-zero-energy-retrofit-beats-my-401k/

Cool Effect, “Mr. Green’s Zero Carbon Home”         https://www.cooleffect.org/content/news/green-testimonial?utm_source=Cool_Effect_CRM&utm_medium=EMAIL&utm_campaign=20180814Engage_Testimonial&utm_content=green_CTA

Green Energy Times, “My Zero Energy Pool is a Great Investment!” http://www.greenenergytimes.org/wp-content/uploads/2019/05/GET_May-2019.pdf

Published Presentations on Zero Carbon Zero Bills:

To see a 3-minute interview of David Green by NBC Boston anchor Joy Lim Nakrin, please click here:TV interview

To see a 20-minute TED talk at Harvard Business School, please click here: TED Talk

You can watch a recorded version of my Zero Carbon, Zero Bills webinar here: Zero Carbon, Zero Bills Webinar

Reviews of my “Zero Carbon, Zero Bills” webinar included, “Minute-for-minute, point-for-point, one of the best webinars I have ever attended. Thank you!”, “David is a true inspiration and asset to our community. He inspired us to get solar panels and a new front door”, “This is like a masterclass in ZeroCarbon”, “Thank you soooo much for the sensible advice and your fabulous resources!!” and, although this next comment is a little flowery, it does express the sentiment of many other comments, “Your contribution to Greening America is great and will probably help our survival as a species a bit longer than expected”.

How big is a ton of carbon dioxide (CO2) / visualizing a ton of CO2

A ton of CO2 gas is huge. It would fill a cube about 27′ (9 meters) on a side. That cube would be as tall as a telephone pole. One ton is the weight of about half a car. In other words, a car weighs about 2 tons.

The carbon footprint of each house in the US varies considerably depending on the location of the house and its size. The following charts show some of this variation. They are taken from, “Goldstein B, Gounaridis D, Newell JP. The carbon footprint of household energy use in the United States. Proc Natl Acad Sci U S A. 2020 Aug 11;117(32):19122-19130. doi: 10.1073/pnas.1922205117. Epub 2020 Jul 20. PMID: 32690718; PMCID: PMC7431053. Which is available here: https://pubmed.ncbi.nlm.nih.gov/32690718/

Useful links:

The Easiest Way to Calculate Your Home’s Carbon Footprint:https://greenzerocarbonhome.com/2018/07/what-is-the-carbon-footprint-of-natural-gas-heating-oil-propane-and-coal/

Written Answers to over 300 Questions about Zero Carbon Homes:https://greenzerocarbonhome.com/webinar-questions-and-answers/

Finance and Net Zero Energy Terms explained: https://greenzerocarbonhome.com/energy-and-finance-terms-explained/

Zero Carbon Home Website Home Page:                https://greenzerocarbonhome.com

Database of State Incentive for Renewable Energy (DSIRE) https://www.dsireusa.org

Published articles on Zero Carbon and Net Zero Energy:

Department of Energy, EnergySage, “Zero Carbon Home”https://www.energysage.com/project/7230/zero-carbon-home/

Zero Energy Project, “My Zero Energy Retrofit beats my 401k”https://zeroenergyproject.org/2018/09/23/my-zero-energy-retrofit-beats-my-401k/

Cool Effect, “Mr. Green’s Zero Carbon Home”         https://www.cooleffect.org/content/news/green-testimonial?utm_source=Cool_Effect_CRM&utm_medium=EMAIL&utm_campaign=20180814Engage_Testimonial&utm_content=green_CTA

Green Energy Times, “My Zero Energy Pool is a Great Investment!” http://www.greenenergytimes.org/wp-content/uploads/2019/05/GET_May-2019.pdf

Published Presentations on Zero Carbon Zero Bills:

To see a 3-minute interview of David Green by NBC Boston anchor Joy Lim Nakrin, please click here:TV interview

To see a 20-minute TED talk at Harvard Business School, please click here: TED Talk

You can watch a recorded version of my Zero Carbon, Zero Bills webinar here: Zero Carbon, Zero Bills Webinar

Reviews of my “Zero Carbon, Zero Bills” webinar included, “Minute-for-minute, point-for-point, one of the best webinars I have ever attended. Thank you!”, “David is a true inspiration and asset to our community. He inspired us to get solar panels and a new front door”, “This is like a masterclass in ZeroCarbon”, “Thank you soooo much for the sensible advice and your fabulous resources!!” and, although this next comment is a little flowery, it does express the sentiment of many other comments, “Your contribution to Greening America is great and will probably help our survival as a species a bit longer than expected”.