Converting a House to Zero Net Energy

Converting a House to Zero Net Energy

Buildings consume 40% of our energy, most of that for heating and cooling. Almost all of this energy is supplied by fossil fuels, resulting in tremendous CO2 emissions. Building electrification solves this problem. Instead of burning fossil fuels in homes and businesses, we can heat, cool, wash and cook using electricity generated from clean, renewable sources.

San Jose is one of the first cities to establish building codes that pursue a  zero net energy policy by strongly recommending all electric new homes. But what about existing homes? To find out first hand what was involved in getting to a zero net energy home, my wife and I embarked on a project to completely electrify our 50 year old home in San Jose.

I’ve done quite of bit of energy upgrading on homes and businesses over the past 40 years. Nevertheless, I checked in with a few friends who had done some electrification of their homes (thanks to Howard, Jeff and Dick). The steps we took mostly followed conventional wisdom: address the easy and cheap items first (LED lights, controls), extra insulation, solar with battery backup, EV charger, heat pump HVAC, heat pump water heater and induction cooktop.

There were only two real hassles with this electrification project. The first hassle is familiar to anyone doing a renovation or maintenance project: finding the “best” contractor for each individual task. Because building electrification involves so many different types of contractors, there is no one “general contractor” who can do everything both efficiently and cost effectively. We ended up with five different contractors: insulation, pool, solar, electrical and HVAC. Since I’m capable of screwing in a lightbulb, I took care of the LEDs lights and controls. The biggest hassle was on the electrical permitting side and coordinating with our local utility. Nevertheless, when everything was done and connected, we are enjoying a net negative (for the year) electric bill — including all of our heating, cooling, cooking and most of our driving.

Perhaps the most rewarding event was when our local gas utility PG&E sent an inspector to our house to find out why the gas meter almost stopped completely! To learn more about electrifying your home or business, please listen to this week’s Energy Show. And if you are thinking about making the switch from fossil fuel home appliances to electrical appliances run by solar and battery storage solutions, take a look at our 10 steps to whole house electrification.

Hidden Barriers to Building Electrification

Hidden Barriers to Building Electrification

Studies show that electrifying our transportation and building sectors are the fastest ways to reducing greenhouse gas emissions. These sectors combined generate nearly 70% of total greenhouse gases in many states, including California.

Our country is making excellent progress in the transportation sector as electric vehicles replace conventional gas vehicles – which generate zero emissions when powered by solar- and wind-generated electricity. Since trucks and buses are larger, it will take a few more years before electrification of these vehicles becomes commonplace. Nevertheless, since average vehicles are on the road for about 10 years, it is entirely feasible to completely electrify California’s vehicles in 10 to 20 years. Without national leadership, this transition will take longer in the rest of the country.

25%of green house gas (GHG) emissions come from the building sector – mostly heating, cooling and lighting. When many buildings were constructed they were heated by fossil fuels, most commonly natural gas for both space heating and water heating. With new heat pump technology it is actually cheaper to heat and cool a building with electricity – resulting in zero GHG emissions if this electricity is generated by solar or wind. Other GHG savings measures — such as LED lighting, better windows and insulation, electric ovens, induction cooktops, and better building controls – are also relatively straightforward to implement.

For new construction, it is easy to build these more efficient and cost effective solutions in. But just in the state of California it will take 50+ years for the approximately 12 million existing single family homes 3 million apartments and 700,000 commercial buildings to completely change over to these new technologies.

Unfortunately, we don’t have 50 years to make this transition – more like 10-20 years if we want to prevent global temperatures from rising more than 1.5 degrees C. On the surface, the key barrier to making this transition is the cost for new vehicles and the cost to retrofit existing buildings. New buildings are relatively easy since building electrification is actually cheaper than space and water heating with fossil fuels.

The real barrier to this transition in existing buildings is the stubborn and selfish attitude of incumbent fossil fuel industries. Architects, builders and contractors are happy to install appliances powered by electricity instead of natural gas. But fossil fuel providers, including gas utilities, oppose these electrification efforts at every opportunity. Just consider the extra costs your utility adds to upgrading your electric service and removing your natural gas connection. Please Listen Up to this week’s Energy Show as we discuss solutions to removing these barriers to building electrification.

Electric Panel Upgrade – With Sue Kateley

Electric Panel Upgrade – With Sue Kateley

To reduce greenhouse gas emissions we need to electrify all of our buildings. New electric appliances — such as heat pumps and induction stoves — are often less expensive to operate than conventional natural gas appliances. For example, at $2/therm for natural gas and $0.30/kwh for electricity, it costs about $1 to heat up a 65 gallon hot water tank for both gas and electricity. Add in rooftop solar and you can heat that tank for less than $0.25!

So from both an economic and environmental standpoint it absolutely makes sense to replace old gas appliances with new electric appliances. Except for one big problem: many older homes have a 100 or 125 amp electrical service — which is insufficient to run most domestic hot water heat pumps, heat pump HVAC systems (heating and cooling), induction electric stoves and level 2 electric vehicle chargers. Not to mention anything other than a relatively small (< 5 kw) rooftop solar power system.

The solution is to contact your electric utility to get an electric panel upgrade to a 200 amp system. Unfortunately, an electric panel upgrade is complicated. Every house is different — some homes have overhead wiring which is relatively easy to replace, and some homes are powered by underground wiring which can take many months and dollars to upgrade.

Navigating the utility and city regulations for electric service upgrades can be a nightmare. To help us understand these issues — as well as the shortcuts and rebates that are available from some utilities — our guest on this week’s show is Sue Kateley. Sue is the former Executive Director of CALSEIA (now known as CALSSA), and has also worked as the Chief of Staff for California State Senator Bradford.

Please listen up to this week’s Energy Show as Sue walks us through her personal experience with PG&E and her electrician as she cost-effectively completed an electric panel upgrade  — and took advantage of some of the little-known incentives and procedures that can make this process much faster and cheaper.


Lose the Gas Furnace, Install a Heat Pump

Lose the Gas Furnace, Install a Heat Pump

Natural gas furnaces for heating are the biggest emitters of greenhouse gases generated by homes and offices. Until recently, these furnaces were state-of-the-art, having replaced oil burners, which replaced coal furnaces, which replaced wood stoves.

Heating, Ventilation and Air Conditioning (HVAC) technology continues to improve. Today, without a doubt, heat pumps are the best way to heat and cool buildings. Most common are air-to-air heat pumps – which basically operate as air conditioners in reverse. Water-to-air (connecting to a well) and ground-source (pipes in the ground) heat pumps are also available.

When your air conditioner dies or your gas furnace expires, you should give serious consideration to replacing these old units with a heat pump system. As part of my Whole House Electrification project, I installed a heat pump, replacing an old gas furnace and dead air conditioning system. The new system has lots of advantages, including efficiency (cheaper to operate than a regular AC and gas furnace), comfort (zoned control), flexibility (easy to set temperatures with an internet-connected thermostat), and super-quiet. The furnace removal and heat pump installation project went smoothly: it took fewer than three weeks from hiring a contractor to turning the new system on.

Installing a new HVAC system can be complicated – not unlike installing rooftop solar and battery storage. To help sort through the details, our guest on this week’s show is Alex Sennert with Supreme Heating and Air. Alex has been in the HVAC business for decades, and does a great job of simplifying heat pump technology, summarizing the economics, and selecting the right solution for your building. If you would like to de-carbonize your home or office with a heat pump HVAC system, Listen Up to this week’s Energy Show.

Home Energy Analytics with Steve Schmidt

Home Energy Analytics with Steve Schmidt

Cities and states all over the country are making a big push to eliminate greenhouse gas emissions in both new and existing buildings. Not only are these changes a necessity to slow down global warming trends, but in many cases building energy costs are also dramatically reduced.

Whole House Electrification (WHE), my latest favorite TLA (three letter acroynum) is accomplished by replacing all gas appliances (including your car) with cleaner and more efficient electric appliances such as heat pumps, EV chargers and electric induction stoves. LED lighting, better HVAC controls and upgraded insulation also help reduce building energy consumption.

But starting a WHE project can be daunting — even for an energy geek like me. Conventional wisdom recommends a home energy audit. When I did my energy audit using the DOE’s Home Energy Advisor program it recommended adding insulation to my stucco walls (almost impossible), sealing my ducts (they were really old), upgrading my old furnace and replacing my noisy air conditioner. None of these recommendations were really right for me.

The reason is that traditional energy audits do not take into account the dizzying array of electric appliances, toys and embedded devices that power our 21st century lifestyle. Most of these energy audits are flat out wrong — ignoring rooftop solar, battery storage, heat pumps and time-of-use electric rates. Combined, these new technologies provide significant savings for an electric home.

Luckily, I found a kindred soul, Steve Schmidt, a pioneer in the new energy analysis industry. Steve founded Home Energy Analytics, which uses smart utility meter data to figure out what is really going on with energy in your house. Please Listen Up to this week’s Energy Show for Steve’s approach to prioritizing and then reducing energy costs, as well as his insights into Whole House Electrification.

Whole House Electrification with Howard Wenger

Whole House Electrification with Howard Wenger

To slow the global warming trend, a number of states have committed to the aspirational goal of 100% carbon-free energy. As a species that literally evolved from burning wood and hydrocarbons, how can we possibly run our modern lives and economy without fossil fuels?

We can indeed achieve this transition quickly and economically. First, by converting all power generation to renewable, non-carbon sources. And second, by converting all fossil-fuel burning vehicles and appliances to electricity. Steady progress towards these conversions is being made. For example, 32% of California’s retail power came from renewable energy in 2018. The state is well on the way to converting to 100% renewable electricity. Use of EVs is growing steadily, and new building codes mandate the use of rooftop solar and electric appliances instead of natural gas.

The challenge is with the existing stock of residential and commercial buildings. Homes and businesses predominantly use natural gas for space heating, hot water heating and cooking. That’s where the concept of Whole House Electrification come in. Whole House Electrification is conceptually simple: replace gas appliances with electric appliances. In reality, one needs an energy audit to prioritize these conversions, then hire five different specialty contractors to do the work: insulation, solar, HVAC, plumbing, electrical and pool. It can be a daunting task.

Fortunately there are some pioneers out there – one of whom is my friend Howard Wenger. Howard was also a pioneer in the solar industry, with stints at AstroPower, PowerLight and SunPower. Please listen up to this week’s Energy Show as Howard discusses his experiences as he converted his house to 100% electricity, supplied — naturally — by solar.