// Numbas version: finer_feedback_settings
{"name": "Calculate annual savings from turning desktop IT off outside of working hours", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "Calculate annual savings from turning desktop IT off outside of working hours", "tags": [], "metadata": {"description": "", "licence": "None specified"}, "statement": "<div class=\"TextLayer-container\">\n<div class=\"textLayer\">\n<p data-start=\"0\" data-end=\"84\">Calculate the annual savings from turning desktop IT off outside of working hours.</p>\n<p data-start=\"86\" data-end=\"94\">Given:</p>\n<ul data-start=\"95\" data-end=\"340\">\n<li data-start=\"95\" data-end=\"165\"><strong data-start=\"97\" data-end=\"118\">{percent_pcs_on}%</strong> of <strong data-start=\"122\" data-end=\"138\">{number_pcs}</strong> PCs are left on <strong data-start=\"155\" data-end=\"163\">24/7</strong></li>\n<li data-start=\"166\" data-end=\"223\">Each PC consumes <strong data-start=\"185\" data-end=\"209\">{pc_power_idle*1000}</strong> W when idle</li>\n<li data-start=\"224\" data-end=\"284\"><strong data-start=\"226\" data-end=\"245\">{hours_working}</strong>-hour working day, <strong data-start=\"264\" data-end=\"273\">5-day</strong> workweek</li>\n<li data-start=\"285\" data-end=\"340\">Electricity cost: <strong data-start=\"305\" data-end=\"332\">{price_electricity*100}</strong> p/kWh</li>\n</ul>\n<p data-start=\"342\" data-end=\"416\" data-is-last-node=\"\"><em data-start=\"342\" data-end=\"416\" data-is-last-node=\"\">Hint: In this calculation, it's fine to have a fractional number of PCs.</em></p>\n</div>\n</div>", "advice": "<div class=\"TextLayer-container\">\n<div class=\"textLayer\"><span role=\"presentation\" dir=\"ltr\" class=\"textLayer--absolute\"> </span><strong><span role=\"presentation\" dir=\"ltr\" class=\"textLayer--absolute\">Energy consumed by one PC running 24/7</span></strong><br role=\"presentation\" class=\"textLayer--absolute\"/><span role=\"presentation\" dir=\"ltr\" class=\"textLayer--absolute\">{pc_power_idle}kW x 24h x 365d = {single_pc_power_247}kWh</span></div>\n<div class=\"textLayer\"><br role=\"presentation\" class=\"textLayer--absolute\"/><strong><span role=\"presentation\" dir=\"ltr\" class=\"textLayer--absolute\">Energy consumed during working hours</span></strong><br role=\"presentation\" class=\"textLayer--absolute\"/><span role=\"presentation\" dir=\"ltr\" class=\"textLayer--absolute\">{pc_power_idle}kW x {hours_working}h x 5d x 52weeks = {single_pc_power_working_hours}kWh</span></div>\n<div class=\"textLayer\"><br role=\"presentation\" class=\"textLayer--absolute\"/><strong><span role=\"presentation\" dir=\"ltr\" class=\"textLayer--absolute\">Wasted energy</span></strong><br role=\"presentation\" class=\"textLayer--absolute\"/><span role=\"presentation\" dir=\"ltr\" class=\"textLayer--absolute\">{single_pc_power_247}kWh - {single_pc_power_working_hours}kWh = {wasted_energy}kWh</span></div>\n<div class=\"textLayer\"><br role=\"presentation\" class=\"textLayer--absolute\"/><strong><span role=\"presentation\" dir=\"ltr\" class=\"textLayer--absolute\">Cost saving for each PC</span></strong><br role=\"presentation\" class=\"textLayer--absolute\"/><span role=\"presentation\" dir=\"ltr\" class=\"textLayer--absolute\">{wasted_energy}kWh x &pound;{price_electricity}/kWh = &pound;{single_pc_savings}</span></div>\n<div class=\"textLayer\"><br role=\"presentation\" class=\"textLayer--absolute\"/><strong><span role=\"presentation\" dir=\"ltr\" class=\"textLayer--absolute\">Cost saving for {dec(number_pcs*percent_pcs_on/100)} PCs</span></strong><br role=\"presentation\" class=\"textLayer--absolute\"/><span role=\"presentation\" dir=\"ltr\" class=\"textLayer--absolute\">&pound;{single_pc_savings} x {dec(number_pcs*percent_pcs_on/100)} = &pound;{total_cost_savings}</span>\n<div class=\"endOfContent textLayer--absolute\"></div>\n</div>\n</div>", "rulesets": {}, "extensions": [], "builtin_constants": {"e": true, "pi,\u03c0": true, "i": true, "j": false}, "constants": [], "variables": {"number_pcs": {"name": "number_pcs", "group": "Ungrouped variables", "definition": "random(100 .. 600#1)", "description": "<p>Total number of PCs.</p>", "templateType": "randrange", "can_override": false}, "percent_pcs_on": {"name": "percent_pcs_on", "group": "Ungrouped variables", "definition": "random(10 .. 50#10)", "description": "<p>Percentage of PCs left on 24/7</p>", "templateType": "randrange", "can_override": false}, "pc_power_idle": {"name": "pc_power_idle", "group": "Ungrouped variables", "definition": "random(0.04 .. 0.09#0.005)", "description": "<p>The power each PC uses at idle in kW</p>", "templateType": "randrange", "can_override": false}, "hours_working": {"name": "hours_working", "group": "Ungrouped variables", 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"anything", "can_override": false}, "wasted_energy": {"name": "wasted_energy", "group": "Ungrouped variables", "definition": "single_pc_power_247-single_pc_power_working_hours", "description": "<p>Variable to store the energy wasted for a single PC left on idle 24/7 over a year.&nbsp;</p>", "templateType": "anything", "can_override": false}, "single_pc_savings": {"name": "single_pc_savings", "group": "Ungrouped variables", "definition": "wasted_energy*price_electricity", "description": "<p>The cost saving for each PC if turned off outside of working hours.&nbsp;</p>", "templateType": "anything", "can_override": false}, "total_cost_savings": {"name": "total_cost_savings", "group": "Ungrouped variables", "definition": "single_pc_savings*number_pcs*percent_pcs_on/100", "description": "<p>Variable to store the total cost savings.&nbsp;</p>", "templateType": "anything", "can_override": false}}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": ["number_pcs", 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