Natalia Blackburn of Blackburn Engineering is conducting a survey to begin to determine how solar cooking usage may be able to reduce traditional consumer energy demand in the USA. While individual savings may be small, when the big picture is considered, Natalia believes that wide use of solar cookers can add up to substantial savings for utilities. The objective of this study is to develop a set of protocols to measure energy savings and dollar savings attributable to the use of solar cookers in USA residential households.
July 2013, Data Crunching Has Begun: Early Results
Survey Respondent Comments:
I solar cook more when camping than at home. -Sacramento County, CA
I have used a solar oven almost exclusively since 1982. -Pima County, AZ
Although I typically only solar cook on weekends I utilize all of my cookers and store the food in containers to be heated for dinner that week. -Sacramento County, CA
We really use our cookers a lot and consider 9 months to be pretty good. We also cook in the winter…It is a definite fuel savings. In the winter or on partially cloudy days we often use a hybrid method of bringing (e.g. beans) to a boil and then leave them in the solar cooker for hours to simmer. -Delta County, CO
I have been solar cooking for many years & have a lot of experience teaching / training others to use them as well ~ I STILL don’t use any of my cookers on a regular basis here in the US…I always say I will, but just don’t. As a novelty on a sunny day, I love to show off what they can do, but the sun is not reliable enough in SF to use on a regular / reliable basis. -San Francisco, CA
My sense is that our household saves [only a] little in natural gas and electricity costs by solar cooking (especially since we make very little use of air conditioning). I think our savings are more in the area of purchasing lower cost food items, like bags of flour to bake with, instead of prepared loaves of bread. -St Louis, MO
I do lots of haybox cooking. My solar oven was damaged (melted + mis-shapened) when cooking on a 113°day… -Oklahoma County, OK
With a good sky, you can do a lot in six months of the year, and I have successfully solar cooked some foods in January, with ambient temperatures in the 20s (F) and snow on the ground. -Latah County, ID
- Number of USA Solar Cooking Survey respondents : 90
- Number of households in the survey : 89
- Number of contacted people who said that they had solar cooked so little last summer that they preferred not participate in the study : 4
- Number of those people who did become respondents : 2
- Number of USA Solar Cooking respondents who have been solar cooking for more than 2 years : 86
- Number of households in the survey that have been solar cooking for more than 2 years : 85
- Number of USA Solar respondents who voted $2 to a solar non-profit org* : 46
- Number of respondents who stated that the survey was understating the number of “pretty good months” for solar cooking (Question B-3**) : 12
- Average number of “pretty good months” represented in those respondents’ surveys : 6.3
- Average number of months those respondents did solar cook last year : 10.6
*And by the way, Solar Cookers International, Solar Household Energy, Inc., and the Solar Cooker Project (Jewish World Watch) have all sent their thanks.
**Question B-3: “It has been suggested that in [location where respondent lives] there are [#] “pretty good” months for solar cooking…How many days per week during those months did someone in your household use a solar cooker?”
Where Respondents LiveTo enlarge map and scroll
News and Developments
June 2014: Quantifying Energy Savings of Thermal Solar Cookers in U.S. Households has been accepted for publication as a part of the American Solar Energy Society's SOLAR 2014 conference in July. Pre-conference copies of the paper are available by request via contact info below.
October 2012 - April 2013: Surveys were conducted with a fifteen-minute phone interview, or the group of twenty-five questions were answered by email. Over 90 people from all over the US were survey respondents. Thank you to all of you who were respondents.
The Residential Energy Consumption Survey of 2009 (RECS), administered by the United States Energy Information Administration (EIA) indicates that cooking appliances including: range tops, ovens, microwave ovens, and toaster ovens, represent 6.5% of the total electrical consumption in U.S. households. That is 74.1 billion kWhs per year. At a rate of $0.128 per kWh that represents over 9 billion dollars per year.
Residential solar cooking is an emerging technology that has the potential of saving a piece of that energy in sunny climate areas in the USA. Saving 30% of that energy by solar cooking during the 6 prime sun months results in saving $26 per year. To put this amount into a utility company perspective, 50,000 households saving 30% with solar cooking represents 1.3 million dollars or 10,300 megawatt-hours per year. Cost savings would be even greater for residential households in the higher cost energy tiers (a factor of 3 for northern California PG&E residential customers currently). Additional smaller order savings include the air-conditioning energy saved by the household for not having heated the house as much in the summer, and electric demand capacity available to the supplying utility for a household not using as much electricity during peak periods.
In the last decade, those of us in the energy efficiency fields have witnessed acceptance of new more efficient products such as compact fluorescent lights, Energy Star refrigerators, and air-conditioners meeting ever higher California energy efficiency standards. Some of these products save very little for each individual household, but have their impact on the larger scale as more and more households participate. The strategies that successfully encouraged these “now emerged” technologies could be applied to solar cooking as well.
As a start in that direction, this study intends to begin the work of quantifying how much energy a household would save by regularly solar cooking. A review of available literature indicates that some work has been done in this area internationally, primarily by non-governmental organizations evaluating their solar cooker projects in countries with ample sun and impending shortages of wood or charcoal for cooking fires. The author could find but a single study located within the U.S.
Many in the USA solar cook, not because they hope to save a lot of money, but because “it’s good for the environment” and “it’s the right thing to do”. Specific savings are not commonly discussed; they are not easily determined. And small annual savings, such as $26 is not enough to sway most USA consumer decisions in any event. Other people purchase solar cookers primarily as a way to cook food in an emergency situation when utility power or natural gas in unavailable. Many of those solar cookers are stored away until needed. Therefore, it become pivotal that the utilities understand that the energy benefits are better perceived on the larger scale.
The objective of this study is to begin that process which has proven helpful with other “now emerged” technologies. It is to develop a set of protocols to measure energy savings and dollar savings attributable to the use of solar cookers in USA residential households. The study will be undertaken in two phases: the first is an initial solar cooking survey and the second encompasses monitoring and verification of several households that regularly solar cook. As a part of the study a set of results will be presented for each phase. The following questions will be asked about the data that is collected:
- Can the study data shed light upon how many USA households regularly solar cook?
- Can the study’s sample of households which regularly solar cook be compared to average national data in a useful way?
- Can the study’s data be used to provide an estimate of energy saved by a household that regularly solar cooks? Estimate of cost savings?
- Can the data be used to provide an estimate of the additional energy saved of cooling the house less?
- Is an estimate of electric demand reduction feasible?
Plaudits also to...
- Citizens For Solar, Tuscon, Arizona
- Solar Household Energy, Chevy Chase, Maryland
- Cantina West, St. George, Utah
- Those involved with solar cooking work done at UNM, Gallup, New Mexico
- Yahoo SolarCooking Group, lotsa places