Study 1: Questioning of the students

Question being posed

The goal of part 1 of the study was to record the acceptance, as well as the knowledge of hydrogen technologies. The following questions were investigated:

• Question 1: Acceptance of hydrogen technologies – Risk assessment
  * What is the degree of acceptance of hydrogen technologies, specifically hydrogen-powered buses by students?
  * On what does the acceptance of hydrogen technologies depend?

• Question 2: Knowledge of hydrogen technologies
  * What do students associate with "hydrogen"?
  * What knowledge do students possess about the subject "hydrogen"?

• Question 3: Demand for information about hydrogen technologies.
  * Is there a demand for information about hydrogen technologies among students?
  * Which sources of information would students use to become more informed about hydrogen?

Method

Random Sample
A total of 410 students at three secondary schools ('Gymnasium'): One school in the city of Munich, one in the outskirts of Munich and one in Oldenburg. The questionnaire was distributed at the participating schools in 10^th through 13^th grades, and filled out in the classroom (Duration: ca. 30 min.).

Instrument
The following variables were recorded through multiple-choice questions which were answered on a five-point scale:

Acceptance of hydrogen
8 items regarding the acceptance of hydrogen technologies were recorded (for exact wording see table 1). The items were summed up into a scale whose reliability was satisfactory (Cronbach's alpha: > .7)

Environmental awareness
For the measurement of environmental awareness, the following dimensions were observed:

Environmental attitude. 7 items; Cronbach's alpha: > .7; Example item: "If we go on like we have until now, we are steering toward an environmental catastrophe."

Threat of environmental problems. Assessment of 12 environmental problems regarding the degree of their threat; Cronbach's alpha > .7; Question: Below, a few environmental problems are presented. Please assess the threat each problem presents. Example items: "Deterioration of the ozone layer", " species extinction", "Depletion of fossil fuels".

Perceived quality of the environment in own neghbourhood. 9 items; Cronbach's alpha > .7; Example items: "I think that the air in my neighbourhood is harmful to one's health", "The landscape in my neighbourhood is intact".

Individual effectiveness on the environment. 6 items; Cronbach's alpha > .6; Example item: "My energy use does not make a difference".

Environmental practices
Environmental practices were measured through 20 questions. To be precise, the actual practices of the students were not recorded, rather their statements about their own practices. This procedure is chosen in most investigations of environmental awareness, since an observation of practices is too costly (see de Haan & Kuckartz, 1996). An analysis of the factors produced two dimensions of the (reported) environmental practices:

Environmental practices – consumption / rubbish. 7 items; Cronbach's alpha > .7; Example items: "I find it too troublesome to separate my rubbish.", "I pay attention while shopping that the products do not have long transportation routes."

Environmental practices – Mobility. 5 items; Cronbach's alpha > .7; Example item: "I keep driving / riding in an automobile to a minimum as much as possible."

For the measurement of knowledge and need for information, both multiple-choice as well as open questions were used:

Environmental knowledge
General environmental knowledge was measured through 6 multiple-choice and 2 open questions. This involved asking questions about various fuels and questions about those environmental problems which are strongly associated with energy use.

The answers to the open questions ("What causes the greenhouse effect?", "What are the consequences of the greenhouse effect?") were evaluated based on their correctness and comprehensiveness (0-4 points each).

The following four multiple-choice questions were to be answered with "true" or "not true" respectively, where each correct answer was awarded one point:

• The greenhouse effect can be limited by the reduction of CFC emissions.
• The main result arising from the climate conference in Rio 1992 is the recognition of the need for a worldwide reduction of CO₂ emission.
• Low-lying ozone increases the danger of skin cancer.
• The hole in the ozone layer can be minimised in particular by using less energy worldwide.

Finally two questions asked the subjects to assess the demand for energy. The first question asked what percentage of the energy use in Germany do the following areas represent: Private households, Transportation, Industry, and 'small' consumers. The second question asked for an estimate of the percentage of energy use in households for each of the following: Heating, driving, water-heating, cooking / Electrical devices, and lights. These questions were graded with 0,1, or 2 point depending on the correctness of the answers. The questions were summed up as "environmental knowledge" (theoretical minimum: 0; theoretical maximum: 16).

Knowledge about hydrogen as a fuel
Three questions measured the knowledge about hydrogen as a fuel. The essay question was: "Which exhaust gases result from the use of hydrogen as a fuel?" The answer to this question was graded with 0 to 2 points. The following multiple-choice questions could be answered with "true or "not true":

• The energy which is got from hydrogen is based on the same mechanism as the hydrogen bomb.

• Hydrogen cars are already being developed by leading car manufacturers today.

A total score was also calculated for knowledge about hydrogen as a fuel (theoretical minimum: 0; theoretical maximum: 4).

Associations with "hydrogen"
For the association with the subject of hydrogen the subjects were asked to name everything they could think of on the subject "hydrogen". This free-association task was done before the other questions, namely before the acceptance and knowledge questions. The associations were categorised afterward by two evaluators. The following categories were defined:

Chemical knowledge directly related to hydrogen. The associations which were classified into this category were those which contained fundamental chemical knowledge directly related to hydrogen and its combustion reaction (e.g. "water", the formula for water or " Knallgasreaktion" [oxyhydrogen gas reaction] ).

Chemical knowledge indirectly related to hydrogen. This category included associations which represented chemical knowledge with only an indirect or loose relation to hydrogen (for example "hydrogen peroxide").

Hydrogen technologies. This category contained all associations which touched upon the technological use of hydrogen as a fuel (e.g. "fuel for cars").

Zeppelin. Even today the zeppelin Hindenburg's accident is mentioned in the media when reporting about hydrogen technologies. Therefore, a category was set aside for the Hindenburg.

Hydrogen bomb. This category consisted of all associations on the subject of the hydrogen bomb.

Threat / Danger. This was a category for associations which rated the threat or danger from hydrogen or hydrogen technologies (e.g. "danger of explosion").

Positive assessment / Environmental friendliness. This was the classification given to associations which were positive assessments, e.g. associations in which hydrogen was connected to "environmentally friendly" or "low emissions".

Results

Question 1: Acceptance of hydrogen technologies

The first question of Part 1 of the study was to what degree hydrogen technologies are accepted by the students. The acceptance was elicited through 8 items (Table 1), which were each rated on a 5-point scale (1 = disagree completely, 2 = disagree for the most part, 3 = agree partially, 4 = agree for the most part, 5 = agree completely).

Figure 1 shows the means and standard deviations for the acceptance values for each question. Items which determined a disapproval of hydrogen, and thus have a different orientation regarding level of acceptance, were inverted in order to enhance clarity. That means that a high value on the scale represents a high level of acceptance. Thus, the high numbers associated with the statement " I am against a further development of hydrogen technologies as they are too dangerous" (Risks from hydrogen) means that the majority of the subjects did not agree with this item.

Figure 1 Mean values with standard deviations of the acceptance values by the students. A high value always represents a high level of acceptance – the inverted items are marked.

It is clear that the acceptance of hydrogen technologies is all in all very high: Both the use of hydrogen-powered transportation as well as the further development of hydrogen technologies are supported – the mean values for these items are close to the maximum value 5. Two items show a deviation from this positive assessment: The statement regarding spending more money for a hydrogen-powered car got an average response of only partial agreement. This duplicates many findings in environmental awareness research which show that, though environmental questions are accorded a large degree of importance, higher costs for a change in behaviour are only of limited acceptability – this applies to both material costs as well as curtailments in comfort or well-being (de Haan & Kuckartz, 1996; Diekmann, 1996; Diekmann & Preisendörfer, 1992). Recently a perfect example of this hedonism has been expressed in the heated debate over a possible increase in the price of gasoline.

The average score "acceptance of hydrogen technologies", which was made up of all eight items, was 4.04 (standard deviation: .56).

Open questions about acceptance. Complementary to the multiple-choice questions evaluating acceptance, the students were asked to state which impediments, in their opinion, stand in the way of a large-scale introduction of hydrogen technologies. The 549 answers to this question were subsequently categorised (figure 2).

In the view of the students, danger – e.g. danger of explosion – does not play an important role in preventing a large-scale introduction of hydrogen technologies. The category "danger" in this case includes all risks which were named by the students. Danger of explosion was mentioned the most; few students connected other dangers with this technology, for example "poisoning". The costs associated with this technology were mentioned more than twice as often as the danger. This included both individual costs (i.e. for hydrogen as a vehicle fuel) as well as the costs to society (i.e. for further research). Surprisingly frequent was the view by the students that a central obstacle is the lobbying of certain groups. Many mentioned concrete interest groups which, in their view, want to hinder the introduction of this technology: The automobile industry, the oil companies and those politically responsible. In the view of the students, lobbying was considered every bit as important as the high technical cost for the use of hydrogen. The lacking public acceptance and low level of knowledge was named as an obstacle in about 10% of the answers. Of somewhat less importance in the view of the students is the fact that these technologies are not yet fully developed, namely that they are still in developmental stage.

Figure 2 Obstacles which stand in the way of a broader introduction of hydrogen technologies in the view of the students. Frequencies of answers in percent.

On what does the acceptance of hydrogen technologies depend?

This study was also intended to pursue the question as to which persons tend to accept hydrogen technologies and which persons tend not to.

Demographics. Next it was investigated whether connections could be drawn between demographic variables (sex, age) and the acceptance of these technologies.

In fact, it was shown that girls judge hydrogen technologies more negatively than boys to a significant degree (girls: M = 3.87; SD = .53; Boys: 4.17; SD = .53; t = 27.5; p < .001). Until now demographic and social variables have been neglected. However, a tendency has been shown in investigations that women are generally much more critical than men of new technologies (Jungermann, 1990). A larger "feminine scepticism" can also be found for hydrogen technologies. Still, the difference between the sexes is not particularly large; it amounts to approximately one half standard deviation.

A second demographic variable which is of interest is the age of the students. In table 2 it can be seen that the acceptance of the technology is dependant on age (F = 3.75; p < .05). The students over 18 years old tended to accept the technology more strongly than the 14-15 year old students (Scheffe; p < .05). The other differences between age groups were not significant.

Table 2
Acceptance of hydrogen technologies in various age groups. Mean values (standard deviations in parentheses)

Dependence on variables of environmental awareness. In addition to demographic variables the relation between environmental awareness and acceptance of hydrogen technologies was analysed. Are these technologies generally more accepted by persons who assign a high value to questions of the environment, behave in an ecological manner themselves, and know much about the environment? Table 3 shows relationships between these variables and acceptance of hydrogen technologies. Indeed a high level of environmental awareness tends to go along with a greater acceptance of hydrogen technologies. Environmental attitudes, environmental behaviour, and the awareness that the individual's actions can contribute to the improvement of environmental problems (individual effectiveness on the environment) all correlate positively – if not strongly – with the acceptance of hydrogen technologies. In contrast, no relationship could be found between the quality of the environment in a person's own neighbourhood and his / her perception of the threat of environmental problems. A significant, though weak, relationship could be found between the environmental knowledge of the students and their acceptance of hydrogen.

Table 3
Relationships between variables of environmental awareness and the acceptance of hydrogen technologies.

Note. ** = p < .01 (statistically significant)

In order to analyse which specific influence the individual variables have on the acceptance of hydrogen technologies a multiple regression was performed.

It was shown that the following variables correlate with the acceptance when the influence of the other predictors are held statistically constant: 'Environmental knowledge', 'environmental behaviour – mobility', 'environmental attitudes ' and age (table 4). The predictors 'environmental behaviour – consumption / rubbish', 'own effectiveness in the environment' , 'knowledge about hydrogen as a fuel', 'perceived threat of environmental problems', and 'perceived quality of the environment in own neighbourhood', do not independently contribute to adjustment of the variance of the acceptance.

Table 4
Result of the multiple regression for the acceptance of hydrogen technologies as an independent variable. The predictors from table 3 were used. The table contains only those predictors with a significant independent adjustment of the variance.

All the predictors together can only explain 9.6% of the variance of acceptance of hydrogen technologies, meaning these predictors are of only limited use in prediction of acceptance of hydrogen technologies.

Extreme groups comparison. A comparison of the extreme groups was to give further information about what the acceptance of hydrogen technologies depends on. For this comparison two groups were formed: That 25% of the students which accepted hydrogen technologies least and the 25% which accepted the technologies most.

Table 5 shows that these persons indeed do differ from each other in a whole range of variables. As expected the extreme groups did not demonstrate any differences in those variables which do not correlate with the acceptance of hydrogen: in the perceived threat of environmental problems as well as the perceived quality of the environment. In all other variables there were significant differences between the two groups. However the differences were – and this was also expected based on the weak to moderate correlation – not large: The differences do not exceed one half standard deviation by any of the variables.

Table 5
Comparison between 'extreme' groups: Students who have a low acceptance of hydrogen technologies and those who have a high acceptance of them. Mean values (standard deviations in parentheses); Results of the t-tests

Question 2: Knowledge about hydrogen technologies

Due to this technology still being not very widespread it could be expected that among the population there is as a whole very little knowledge about hydrogen technologies. A key result of the study was that this also applies to students in 'Gymnasium'.

Knowledge about hydrogen as a fuel. On the knowledge questions about hydrogen as a fuel there was a maximum of 4 points possible. Figure 3 shows that none of those questioned could reach this total, and only 14 of the students (from a total of 410) were able to get 3 points.

Figure 3 Results of the knowledge tests about hydrogen as a fuel. Frequency graph of the points achieved in the knowledge test.

Associations with hydrogen. At the start of the questions the students were asked to note their associations with the term "hydrogen". One goal was to investigate whether knowledge-related associations would be mentioned by the students and if so, which ones; another item of interest was which judgemental associations would be mentioned. Overwhelmingly positive or negative associations? Is hydrogen, for example, often associated with "threat"? In order to answer these questions, a measure for the relative frequency of the individual categories of associations was worked out: For each test subject it was determined what percent of their associations fell into a particular category. Mean values for each category were then calculated from these values and are graphically presented in figure 4.

Figure 4 Frequency in percent with which specific content was named on the average by the students in their associations.

The large majority of the expressed associations applied to chemical knowledge directly related to hydrogen and its combustion reaction. However, very many of these associations were rather superficial; for example "water" or "Knallgasreaktion" (oxyhydrogen gas reaction). Approximately 7% of the associations mentioned were also of a chemical nature, but were not related to hydrogen as a fuel (e.g. hydrogen peroxide). Nearly 11% of the associations had to do with hydrogen technologies (e.g. "rocket fuel"). Only 0.3% of the associations explicitly mentioned "zeppelin", "Hindenburg" etc.

The judgemental associations confirmed the results of the acceptance questions: Both threatening associations (e.g. explosive or dangerous) and associations with the hydrogen bomb were relatively seldom. However positive, environment-related associations where the environmental friendliness of hydrogen was emphasized barely arose. Approximately 8% of the statements could not be categorized.

It was also investigated in which categories the two 'extreme' groups (see above) differed from eachother (table 6):

Table 6
Mean values (standard deviations parentheses) of the frequencies in percent, with which the specific categories of associations were mentioned by individual test subjects. Comparison of the two 'extreme' groups; results of the variance analysis.

Of interest is that there were no relevant differences between the two groups as to the proportion of associations in which chemical knowledge directly related to hydrogen was expressed. Nevertheless, students with a higher level of acceptance mentioned associations with "hydrogen technologies" far more frequently and and associations with "environmental friendliness more frequently (Note: The questions on the associations were asked at the start of the investigation and collected immediately afterwards). Still, associations with threatening aspects of hydrogen or with the hydrogen bomb occured with the same frequency as they did with the persons who evaluated hydrogen technologies negatively. It can be assumed that also the persons with a high level of acceptance perceive the risks, but that the aspects of environmental protection outweigh the danger in their assessment of technologies. The results also indicate that persons who are familiar with hydrogen technologies are more liable to accept them, even when they are aware of the risks. This indicates a certain familiarisation effect.

Regarding the question of the knowledge it is appropriate to also compare the three schools with eachother, as the school in Oldenburg has somewhat of a special role. At this school there is a teacher who is engaged in advocating the topic "hydrogen technologies", and who also saw to distributing the questionnaires. A majority of the students who were questioned had already dealt with the topic "hydrogen technologies" in class. Nevertheless, it can be seen from table 7 that regarding knowledge about hydrogen technologies they did not differ from the students in Munich – though they indeed differ regarding their acceptance. The Oldenburg students demonstrate a significantly more positive acceptance value than the students at the Munich schools (Scheffé each p < .05). Still, the differences between these two groups is about one half standard deviation – thus, they are not so large.

Table 7
Differences between the different schools. Mean values (standard deviations in parentheses). Results of variance analyses.

Now, it is surely hasty to draw the conclusion from these results that instruction on the subject of hydrogen is ineffective in fostering knowledge about the subject. For one, it would have to be analysed in a more detailed manner, which content at what interval before this investigation had been taught in instruction. For another, it is also all too well-known from other studies – particularly dealing with natural sciences – how stubbornly "naive concepts" are held to despite instruction (see for example Smith, diSessa & Roschelle, 1993). But the differences in the level of acceptance of one half standard deviation are certainly remarkable: Further investigations should pursue the question more specifically of what effect instruction has on the knowledge and acceptance of hydrogen technologies. For example the question could be investigated as to which "naive concepts" about hydrogen change under which (instructional) conditions.

Question 3: Demand for knowledge about hydrogen technologies

Due to the extremely meagre results of the knowledge tests it could already be expected that the students would notice in themselves a great need for knowledge on this subject. The data confirm this: Approximately 70% of the students agreed to the item "I would like to have more information about hydrogen technologies" either partly or fully (M = 3.93; SD = 1.15; see figure 5).

Figure 5 Answers to the item "I would like to have more information about hydrogen technologies." Frequency.

The students were furthermore asked, whether they had already received information about hydrogen technologies. Somewhat more than half (208) answered that they had neither heard nor read any information – 185 students had already, and 17 gave no answer to this question. Figure 6 gives an overview of the sources from which students had their information – if any.

Figure 6 Past sources of information on hydrogen technologies for the students. Relative frequencies in percent of the named information sources.

The most common source of information about hydrogen was the mass media, namely television, newspapers, magazines, and radio. The Internet as mass media is not expressly mentioned in any of the statements. The second most important information source was the school – approximately 30% of the students questioned have already learned something about hydrogen technologies in class. All other sources of information are of secondary importance.

We also asked the students what information source they would use if they wanted to become more informed about hydrogen technologies (figure 7).

Figure 7 Potential sources of information about hydrogen technologies if researching them specifically, as named by the students. Relative frequencies in percent of the named information sources.

Most of students questioned would turn to a teacher if they wanted to know more about this subject. In many statements a teacher of chemistry or physics was named – a fact which underscores the importance of teacher education in these fields. In 63 statements students specifically said that they had no idea how to get information about hydrogen. Since 78 students gave no answer to this question, it is probable that the ratio of students who would not know to whom they should turn for further information is considerable. A way out of the "helplessness" seemed for many to be asking for information at the university or a research institute. The logo of the University of Munich was quite visible on the questionnaire – it is doubtful that the students would indeed turn to a university if they wanted more information on the subject. The fact that environmental protection organisations enjoy a high level of trust on questions of the environment is already known from other investigations (see de Haan & Kuckartz, 1996). Also for the subject of "hydrogen technologies" organisations of this sort (e.g. Greenpeace) are named more frequently than, for example, state or community institutions.

Based on their statements students would also fall back on the Internet relatively often when searching for information about hydrogen technologies. If they have realised this plan in the weeks after the investigation, the visitor numbers at the Internet pages of HyWeb must have certainly climbed. In any case it is clear that the Internet is considered by young people to be a chief source of information for scientific questions – all the better that young people's need for information can be covered in this medium.

Discussion

In summary, the results show a surprisingly high level of acceptance of hydrogen technologies by students. The further development of hydrogen technologies for mass production and the use of hydrogen-powered vehicles is predominantly welcomed. However, the high costs of hydrogen-powered vehcles – particularly individual costs, i.e. for automobile fuel – are perceived as problematic.

It is conspicuous that danger of explosion was only named seldomly as a spontaneous association. When the students were explicitly asked to assess the explosion danger of this technology, they tended to judge it as explosive. It is possible that the item "Technologies with hydrogen are connected with a greater danger of explosion" (presented after the association) was responsibles for informing the students that this danger even exists, and induced a corresponding assessment of risk. This interpretation is also supported by the astonishingly low level of knowledge of students about this subject. It also known from other fields that information about risks can often have a contraproductive effect. Even when the information is supposed to make it clear that the risk is very low, the effect can be just the opposite, and the assessment of danger climbs rather (Jungermann & Slovic, 1993).

The acceptance of hydrogen-powered vehicles proved to be slightly dependent on sex, age, and a few variables of environmental awareness. Boys, older students and environmentally aware persons tend to accept these technologies more. However, it must emphasised that these predictors can only marginally predict the acceptance: The adjustment of the variance is very slight. Thus, further inestigations should pursue the question of which variables can be used to better predict the acceptance of hydrogen technologies.

The level of knowledge about hydrogen technologies was astonishingly low – and the demand for information on this subject correspondigly high. Two things are noticable about the potential sources of information for this subject: The school was named very frequently as a potential deliverer of information. This makes clear that the subject "hydrogen technologies" should be taken more heavily into consideration in teacher education. This applies particularly to teachers of Physics and Chemistry, who were specifically named by students. The students also named the Internet as an important resource. From that it could be concluded that HyWeb – the information system about hydrogen in the Internet – will indeed be used where the interest exists on the part of the students.