Every day, I strive to Make Energy CENTS from the Home to the Globe. Whether programming the thermostat to low temperatures overnight to providing comments on national energy policy drafts to opening discussions as to Energy COOL technologies and concepts, my efforts to Energize America to a prosperous, climate friendly future cross a broad spectrum.
To be clear and blunt: there is NO SILVER BULLET solution. In my own life, every year sees more ‘investment’ in energy efficiency, new ways to think about / execute conservation from what food we buy to our travel choices, and ways to help remediate the damage I inevitably cause to the planetary system’s ability to support my children’s children to the seventh generation and beyond.
We need to approach the challenge in a holistic manner and remember Three Rs:
1. Reduce …
This diary focuses on a portion of the second, “renew”, and how renewable power is playing an increasing role in my household’s life … more specifically, outlining some of the “solar” products at home.
When people say “solar power”, the eyes look up and to the roof. Active solar power isn’t the first thing to do (curtains, lighting, etc …), but looking up to my roof you will see:
- Solar hot water: I have two 4 x 10 collectors which feed into a 80 gallon storage tank which then feeds into a 40 gallon natural gas tank. The solar hot water system also supports a (small) radiator heating system, thus not just the personal hot water use. Current estimate is that this covers about 70% of use. The coolest part of the system is the utter absence of pumps or other electrical equipment to run it. The Sunnovations system is a pressure-based system which eliminates the need to run a pump at any point during the system’s life (or cover the collectors when away from home for more than a few days). Writ large, watt-hour by watt-hour, a less energy-intensive and less costly (no pumps to run or replace) solar system. This is a less expensive to install and less expensive to operate system than many other solar hot water systems.
- Solar PV: Just installed by Edge Energy a few weeks ago (active on 8 July), this 24 panel system uses Enphase microinverters with a total of 4.7 kw AC (5.5 DC) total capacity with south and east facing panels. This should result in between 6 and 7 megawatt hours/ year of electrical generation that will cover 85-100+ percent of the household energy demand which is about 60% of the average in my state (even with a home office and a full household).This is a grid-tied system, with the Commonwealth of Virginia’s ‘net metering’ meaning that the meter can run backwards when the system is producing more than we’re using and, well, the ‘normal’ direction when the solar pv isn’t do so well (like at 2 am). We can’t turn a profit but we can erase our power bills.One of Energy COOL things about enphase? The ability to track the power generation in real-near time. (See here for the SIEGEL home.) Right now, this Enphase addict is probably averaging a good 10+ times per day checking the systems productivity. And, the tracking system enables downloads of data for a wide range of manipulation/analysis options.
Solar Cone for composting
As discussed in Energy Home: Composting with a Cone, composting is a part of life likely learned while in the womb. Rats exiled from a closed restaurant forced me to find a new composting method and Solar Cone’s “Green Cone” provided the answer. These double-layered cone (with basket well underground) uses the sun’s rays to help cook the composting mix to higher temperature, leading to a faster decomposition.
Solar light tubes We did a small addition and wanted as much natural lighting as well but the cost (and other problems) of sky lights put us off but solar light tubes provided a great solution. Even on a cloudy day the results were beyond expectations. A small, 10-inch tube, and the laundry room never needs a light on during the day. Every visitor to the house gets their tour of the laundry, wondering why I insist on closing the door on us in the laundry room as I excitedly talk about how wonderful they are. With an image out of Lost in Space, the domes of our three light tubes stick above the roof. And, well, it is near impossible to leave a light on all night by accident. If the light tube works wonderful at reflecting sunlight into the house, it does just as good a job at reflecting light out. Thus, during the day, my interior spaces are brightened by the sun and, sadly, when the lights are required at night, my solar tube/light combinations form an effective searchlight, adding to the community’s light pollution. Hmm … the world is complex … solve one problem and create another?
Solar cooker: Solar cooking is truly an Energy COOL arena that doesn’t get enough attention or, well, support. Truth be told, few around the world could count on solar cookers for all of our cooking but with integrated cooking (solar plus fuel-efficient non-solar cooking), we could drastically reduce the polluting energy inputs into cooking. And, you don’t need to go high-end or commercial product to have a workable stove. (For great and informative videos, see solar wind mama (who is on the board of Solar Cookers International). Now, cooking in the stove in the photo: boiling eggs; and a try at chicken roast that turned out to be a delicious chicken stew. (Yes, I admit it, I have no problem with the simple solar cooking but have yet to get more complicated recipes ‘right’.)
Total Cost of Ownership
Now, the “cost” equations are pretty difficult with all of the above but the discussion would be incomplete without the discussion. Question 1 would be ‘what did X (or Y) cost you’? Reality is, however, that this misses the equation. That upfront “cost” absolutely matters, but it really is an equation of the long term costs and what the “payback” periods might be. And, there are (of course) many other benefits — such as my kids stating, firmly, that “we have the coolest house on the street” or the number of people who ask questions about the solar systems. And, well, it does feel good to check the # of kwh/day (26.7 kwh today as I type this) and see the meter go backwards. Thus, the costs and benefits are far from just directly financial in nature. In any event …
1. Solar PV: After Federal and Commonwealth assistance, the purchase cost is about $13,000 (lots of complexity as to why “about” and it isn’t all settled). The annual electrical savings should be $600-$700 with net metering and the annual solar renewable energy credits could be $1200 to $2000+. There is an added cost of $48 / year for Enphase subscription. All told, it could “pay” for itself in perhaps 7 years with free electricity to come after that.
2. Solar DHW: Again, complicated because we put in the solar DHW, a 120 gallon storage tank, a new gas water heater, a switching system to control water flow into our (small) radiant heated floor, and had a good amount of piping reworked. All told, after Federal tax credit, about $6000. Now, the replaced gas water heater was about to go belly up and would have needed replacement — drop that cost by easily $1000. Hard to track exact savings, as we have gas heating and hot water but it looks to be about $400 / year. And, my county provides about $90 in reduced real estate taxes for five years. Even including the extra pipe work, this is about a 12 year payback period — which is, again, longer because this calculation includes non-solar DHW work. (A Sunnovations, only, installation would have had a far faster payback period.)
3. Solar light tubes: We put three in when doing a (SMALL) extension with the cost about $550 for purchase and installation. We might be saving $10 or $25 or $50/year in reduced electricity bills (one of the rooms with a light tube is interior yet, unless it is night, the light is never on). And, if there weren’t the light tubes, we would have installed extra lights (there are lights in the tubes that can be turned on). Again, hard to get to $s payback period.
The composting and solar cooking clearly aren’t $ payback items — especially since they were both provided by the manufacturer for review purposes — but in neither case is the $ savings a primary element of the equation.
Note on resources: Solar PV remains out of the reach for most Americans. With the Commonwealth of Virginia putting stimulus package money into helping homeowners buy renewable power, it became ‘affordable’ for us. My better 95+% and I also are in the fortunate situation of having bought our home before market insanity hit and had significant equity in the house, enabling a refinancing to pay for the solar pv and hot water and put these investments in the home on a long-term payback cycle (that also cut the interest rate by 7/8ths percent). The savings from the solar pv and the solar DHW are greater than our additional mortgage cost — thus, these systems are ‘paying for themselves’.
And, to be clear, while I obviously see solar as part of the solution path forward (and decided to put my hard-fought $s where my mouth (or keyboard) is), solar power is not the solution … I do not see any Silver Bullet solutions but, rather, a smorgasbord of opportunities that can combine to foster a prosperous, secure, and climate-friendly future for America.